The U.S.-Iran MOU Is a Welcome Step; Now Negotiators Must Focus on Practical Nuclear Nonproliferation Diplomacy

Statement by Kelsey Davenport, Director for Nonproliferation Policy

For immediate release: June 15, 2026

Media Contacts: Kelsey Davenport (202-463-8270 ext 102); Daryl G. Kimball (202)-463-8270 ext. 107)

Reports that the United States and Iran finalized a preliminary deal to halt the war is a welcome development that creates a pathway for resuming negotiations on Iran's nuclear program that were underway when the United States and Israel launched their illegal attack on Iran on February 28.

The NPT Review Conference Must Address the Disarmament Deficit

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The NPT Review Conference Must Address the Disarmament Deficit

NGO Statement for the 2026 Review Conference on Article VI-Related Goals and Objectives

For more than five decades, the nuclear Nonproliferation Treaty has served as the essential framework and catalyst, albeit an imperfect one, for global efforts to stop the spread of nuclear weapons, end nuclear testing, reduce the salience of nuclear weapons, and advance disarmament diplomacy to help achieve a world free of nuclear weapons.

But now, due to years of inattention, inaction, and reckless disregard for international norms of behavior by some NPT nuclear-armed states, the nonproliferation system is facing an uncertain future. States-parties at the past two NPT review conferences, in 2015 and 2022, have failed to overcome differences that have blocked agreement on measures to advance treaty goals.

To be successful, this NPT Review Conference must address the “Disarmament Deficit” and help deliver tangible commitments from the five NPT nuclear armed states that help put us back on the path to reducing nuclear dangers and toward the peace and security of a world without nuclear weapons.

This makes it essential that your delegations:

  • Work together to reaffirm your governments’ support for the treaty, and to the principles, objectives, and action steps that were endorsed by consensus at the 2010 and 2000 review conferences and at the pivotal 1995 Review and Extension Conference.
  • Agree to achieve concrete action steps that reduce the nuclear danger and advance the NPT’s core Article VI disarmament-related objectives.

As this meeting convenes, the disarmament deficit is growing. None of the NPT’s nuclear-armed five can credibly claim they are meeting their key NPT Article VI commitment to “pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament,” nor have they met all of the disarmament-related goals and objectives agreed to at the 1995, 2000, 2010 NPT Review Conferences.

  • New START has expired with no replacement. As a result, for the first time in decades, there is no legally binding treaty or mutual understanding limiting the size and composition of the U.S. and Russian strategic nuclear arsenals, the world’s largest.
  • Independent researchers confirm that China continues to expand its arsenal.
  • France has just announced it will also begin to increase the size of its arsenal, which violates the principle of “irreversibility” that past NPT conferences have endorsed.
  • There are no active negotiations between or among the five nuclear-armed NPT states on disarmament. (The P5 Process is not a negotiating forum at this point.)
  • Each of the NPT’s nuclear-armed states are spending tens of billions of dollars to modernize, upgrade, and in some cases increase the size of their deadly nuclear arsenals.
  • The CTBT, which is a central element of the NPT system, is at risk. The United States has threatened to resume nuclear explosive testing “on an equal basis” and has accused another, China, of conducting a prohibited nuclear test. Nine states have failed to ratify the CTBT; some have failed to provide a credible explanation as to why they remain holdouts. As a result, these states are holding up entry into force and are denying themselves and the world the option for on-site inspections, which can effectively resolve allegations of and deter any possible clandestine, low-yield nuclear explosive testing.
  • The wars against Ukraine and Iran, which involve nuclear-armed states illegally attacking nonnuclear weapon states, further highlight the failure to make progress toward legally binding negative security assurances. They are also a reminder that the United States has not yet ratified the protocols to three nuclear weapon free zones – the African, Central Asian, and South Pacific. As a result, the negative security assurances associated with these agreements are not yet in force.

Worse yet, with China’s nuclear buildup in mind, many members of the U.S. nuclear-weapons establishment are lobbying for a buildup of U.S. nuclear forces, starting with uploading additional warheads on existing ground-based intercontinental ballistic missiles and by adding sea-based nuclear-armed missiles on strategic submarines. Independent experts estimate that the United States, as well as Russia, could potentially add hundreds of warheads to their already deployed strategic delivery systems.

More nuclear weapons will not make anyone, anywhere, safer. Each of the world’s nuclear-armed states have more than enough nuclear weapons to meet their subjective requirements for nuclear deterrence and certainly enough nuclear weapons, if used, to produce catastrophic destruction on a global scale.

Halting the spiral of nuclear tensions and a renewed buildup of nuclear weapons is in every nation’s interest. This requires more than vague pronouncements and promises; it requires concrete commitments and follow-through actions on disarmament diplomacy.

It is tragic that U.S. and Russian leaders failed to engage in meaningful negotiations on a successor agreement to New START. It is also notable that following the expiration of New START, the United States proposed multilateral strategic stability talks as a means to achieving a “new era” in nuclear arms control.

Such an approach may sound appealing. Indeed, all five NPT nuclear-armed states have Article VI obligations. But without a serious strategy for success, this could be a formula for further inaction, especially given the complexities of a five-sided negotiation involving states with different force sizes, force structures, nuclear postures, and strategic cultures. The “P5 Process,” which has been underway since 2007 has little to show for its efforts.

Nevertheless, we would hope that multilateral negotiations on disarmament involving all five nuclear-armed NPT states, if launched, might produce meaningful results. But such an initiative should not be allowed to substitute for the immediate commencement of serious bilateral talks between the United States and Russia and the United States and China on nuclear risk reduction, strategic stability, and nuclear arms reductions that could also yield concrete arms control and risk reduction outcomes, and perhaps more quickly.

To improve the chances of success in future arms reduction talks, however they may be pursued, and to prevent unconstrained nuclear competition, we call on all five NPT nuclear-armed states to agree to freeze their strategic launchers at their current numbers.

As of now, Russia and the United States each have fewer than 800 total strategic launchers; China has an estimated 550, including unfilled strategic missile silos; and France and the United Kingdom have a combined total of about 96. A freeze on strategic nuclear launchers at these levels would not adversely affect any one country’s ability to deter nuclear attack, and could be more easily verified through remote, national means of intelligence.

Recommendations

We call on all states parties to come together on a final conference outcome document that:

  • Reaffirms that all states recognize their obligation to accomplish the total elimination of nuclear weapons and through practical steps on nuclear disarmament and nuclear non-proliferation as agreed to by consensus at the 1995, 2000, and 2010 Review Conferences.
  • As an urgent next step and commensurate with Article VI of the Treaty, calls upon the nuclear weapon states to engage, no later than the end of 2026, in good faith negotiations, bilaterally and/or multilaterally, that are designed to end the nuclear arms race and toward nuclear disarmament and to refrain from increasing the size of their nuclear arsenals.
  • Urges the states with the largest nuclear arsenals to re-engage on nuclear disarmament negotiations and conclude a new framework agreement (or agreements) addressing strategic, intermediate-range, and nonstrategic weapons and seek new understandings on the interrelationship between strategic offensive and defensive weapons.
  • Reaffirms support for the de facto global moratorium on any and all nuclear explosive tests that has been solidified under the “zero-yield” CTBT, which prohibits all nuclear explosions that produce a self-sustaining supercritical chain reaction of any kind whether for weapons or peaceful purposes. Any resumption of nuclear explosive testing particularly by one of the NPT’s nuclear five, would violate the moratorium and the CTBT, and could set off a chain reaction of nuclear testing that would blow apart the global nonproliferation system.
  • Calls for prompt action on ratification before 2030 by the remaining CTBT Annex 2 states, in particular China, Russia, and the United States, and also calls upon the five nuclear-armed NPT states to promptly commence technical discussions to develop new mutual confidence building measures to be implemented prior to CTBT entry into force to ensure that ongoing activities and experiments at former nuclear test sites are fully consistent with the CTBT.
  • Finally, the final conference outcome document should reaffirm the nuclear-armed states’ previous commitments to non-nuclear-weapon states against the use or threat of use of nuclear weapons, it should call upon relevant states to ratify the protocols to nuclear weapon free zone treaties by 2027, and call upon relevant states parties to facilitate the immediate start of negotiations at the Conference on Disarmament on a legally binding international instrument that obligates nuclear-armed states not to use or threaten to use nuclear weapons against non-nuclear-weapon States parties to the NPT.

Distinguished delegates: This is no ordinary NPT meeting. The results of the 2026 NPT Review Conference will likely have profound, long-term effects on our common future for many years to come.

We wish you success and offer our help and support.

Respectfully,

Elizabeth Hume, Executive Director, Alliance for Peacebuilding

Mohamed AL SHAMI and Ahlam Lamrani, Alliance Internationale pour la Défense des Droits et des Libertés (AIDL)              

Daryl G. Kimball, Executive Director, Arms Control Association

Peter Wilk, Administrative Chair, Back from the Brink Coalition                   

Max Obuszewski, founder, Baltimore Nonviolence Center              

Joseph C. Gerson, President, Campaign for Peace, Disarmament, and Common Security      

Matt Duss, Executive Vice-President, Center for International Policy*

Nancy Okail, President & CEO, Center for International Policy    

Paul G. Richards, Professor of the Natural Sciences emeritus, Columbia University*

Rachel MacNair, Vice President, Consistent Life Network  

Oliver Meier, Head Nuclear and Multilateral Disarmament, European Leadership Network*            

Goetz Neuneck, Prof. Dr., Federation of German Scientists           

Michele Sterlace-Accorsi, Executive Director, Feminists Choosing Life of New York, Inc.          

Jenifer Mackby, Nonresident Executive Fellow, Geneva Centre for Security Policy*

Thomas Greminger, Ambassador, Geneva Centre for Security Policy (GCSP)*

Mary Olson, Founder and CEO, Generational Radiation Impact Project

Steve Baggarly, Member, Hampton Roads Campaign to Abolish Nuclear Weapons      

Jean-Marie Collin, Director, ICAN France    

Sean Conner, Executive Director, International Peace Bureau (IPB)          

Michael Christ, Executive Director, International Physicians for the Prevention of Nuclear War            

Hideo ASANO, Coordinator, Japan Campaign to Abolish Nuclear Weapons       

Yerdaulet Rakhmatulla, Founder & CEO, JASA*

David Cortright, Professor Emeritus, Kroc Institute for International Peace Studies, University of Notre Dame*

Dr. Deepshikha Kumari Vijh, Executive Director, Lawyers Committee on Nuclear Policy   

Laura S H Holgate, Former United States Ambassador to the International Atomic Energy Agency and the Preparatory Commission of the Comprehensive Nuclear-Test Ban Treaty Organization, LSHH International Advisors  

Benetick Kabua Maddison, Executive Director, Marshallese Educational Initiative                          

Susan F. Burk, former Special Representative of the U.S. President for Nuclear Nonproliferation

Thomas Countryman, former U.S. Assistant Secretary of State for International Security and Nonproliferation

Julia Hurd, Steering Committee Member, No More Bombs             

Irma Argüello, Founder & Chair, NPSGLOBAL Foundation               

Dimity Hawkins, Program Coordinator, Nuclear Truth Project      

Estelle Voeller, Chair, One Sunny Day Initiatives   

Kevin Martin, President, Peace Action          

Rebecca Irby, Founder and President, PEAC Institute Peace | Education | Art | Culture

Akira Kawasaki, Executive Committee Member, Peace Boat         

David E Gibson, Co-Director, Peace, Justice, Sustainability NOW             

John Hallam, Nuclear Disarmament Campaigner, People for Nuclear Disarmament  

Magritte Gordaneer, Director, Nuclear Weapons Abolition Program, Physicians for Social Responsibility     

Shaghayegh Chris Rostampour, Policy and Communications Manager, Physicists Coalition for Nuclear Threat Reduction*

Bill Kidd, Member of the Scottish Parliament, PNND*

Frank N von Hippel, Professor of Public and International Affairs Emeritus, Princeton University*

Stewart Prager , Professor emeritus, astrophysical sciences, Princeton University*

Robert Goldston, Professor, Princeton University*

Lucy W Duff, Member, Prince George's County MD Peace Action

Lauren Pope, Executive Director, Rehumanize International         

Robert M. Gould, M.D, President, San Francisco Bay Physicians for Social Responsibility       

Paul Meyer, Adjunct Professor of International Studies and Former Canadian Ambassador for Disarmament, Simon Fraser University*

Tomohiko Aishima, Executive Director, SGI Peace Center, Soka Gakkai International 

Diane R. Swords, Steering Committee Member, Syracuse Peace Council            

Jennifer Allen Simons, Founder and President, The Simons Foundation Canada*

Scott Yundt, Executive Director, Tri-Valley Communities Against a Radioactive Environment (CAREs)              

Ana Palada, United Network of Young Peacebuilders*

Frederick K. Lamb, Research Professor of Physics and of Astronomy, University of Illinois*

Tara Drozdenko, Director of Global Security Program, Union of Concerned Scientists

Rev. James L Swarts, President, Veterans for Peace, Chapter 23, Rochester, NY             

Ken Lans, MD, MBA President, Washington Physicians for Social Responsibility             

Jacqueline Cabasso, Executive Director, Western States Legal Foundation        

Robert Croonquist, Co-Founder, Youth Arts New York/Hibakusha Stories

*Affiliation for identification purposes only.

**This statement was coordinated by the Arms Control Association.

Reinforcing the Prohibition on Nuclear Explosive Testing and the CTBT

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Reinforcing the Prohibition on Nuclear Explosive Testing and the CTBT

Joint NGO Statement* for the 2026 NPT Review Conference, May 1, 2026

For decades, a global ban on nuclear explosions has been a central goal and is now a central element of the nuclear nonproliferation and disarmament regime because an effective, comprehensive, verifiable test ban directly constrains the ability of all parties to develop new or more-advanced nuclear weapons.

The push to end all nuclear test explosions has also been driven by the widespread human suffering and environmental contamination produced by more than 2,000 atmospheric and underground nuclear test explosions since 1945. Hundreds of thousands of people have died and millions more have suffered— and continue to suffer—from illnesses directly related to the radioactive fallout from past nuclear detonations in the southwestern and western United States, islands in the Pacific, in Australia, western China, Algeria, across Russia, across Kazakhstan, India, Pakistan, the DPRK, and elsewhere.

While the CTBT and the de facto global nuclear testing moratoria have helped to reduce health and environmental injury from further nuclear-weapons testing, the effects of these detonations are still taking their toll on impacted communities across the globe.

Universal compliance with "zero-yield" prohibition on nuclear explosions established by the 1996 Comprehensive Test Ban Treaty is essential to the future of the NPT and global peace and security.

In the negotiations for the 1968 Treaty on the Non-Proliferation of Nuclear Weapons (NPT), a comprehensive test-ban was widely recognized as a critical part of the nuclear-weapon states’ obligation to meet their NPT Article VI commitment to “effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament.”

The preamble of the NPT specifically cites the goal of “the discontinuance of all test explosions of nuclear weapons for all time and to continue negotiations to this end.” And in 1995, NPT states parties agreed to indefinitely extend the treaty on the basis of the commitment to complete multilateral negotiations on the CTBT by 1996.

Not only did NPT states parties reaffirm their commitment to the CTBT at the 2000 and 2010 Review Conferences, but international support for the CTBT has been reaffirmed over the years through multiple UN General Assembly resolutions and UN Security Council (UNSC) resolutions.

UNSC resolution 1887 (2009) calls upon all states “to refrain from conducting a nuclear test explosion and to sign and ratify the Comprehensive Nuclear Test-Ban Treaty, thereby bringing the treaty into force at an early date.”

On the occasion of the twentieth anniversary of the opening for signature of the CTBT in Sept. 2016, the UNSC adopted the first-ever, CTBT-specific resolution (UNSC 2310), which reaffirms the global norm against nuclear-weapon-test explosions, calls on the eight remaining states that must ratify for entry into force to do so, and urges all states to provide their full financial and technical support to the CTBTO. The resolution was formally co-sponsored by forty-two states, including Israel.

The UNSC 2310 test-ban resolution also formally recognizes the important September 15, 2016, statement from the permanent five members of the council expressing the view that any nuclear test explosion would “defeat the object or purpose of the treaty.” The statement gives public expression to the existing legal obligation of all CTBT signatories not to test a nuclear weapon, even before the treaty enters into force.

Three decades after the conclusion of the CTBT, the treaty has near universal support and has established a global norm against nuclear test explosions. The nuclear testing taboo contributes to both nuclear nonproliferation and disarmament. It impedes the development of new and more advanced nuclear warhead designs, which helps prevent dangerous nuclear competition and strengthens international security. 

The New Dangers to the CTBT and the De Facto Global Nuclear Test Moratorium

But the CTBT and the de facto global nuclear test moratorium cannot be taken for granted.

It is well known that the treaty's entry into force has been delayed due to the failure of eight key states, including the United States and China, to ratify, and Russia’s cynical decision to “de-ratify” in 2023.

Even though all 187 signatories are legally bound to respect the object and purpose of the treaty, the full benefits of the treaty – including the option to order short-notice on-site inspections to investigate potential violations – cannot be realized until it enters into force.

Additionally, the CTBT and the global nuclear test moratorium are now facing unprecedented new challenges related to:

  • concerns about ongoing activities at former Russian, Chinese, and U.S. nuclear test sites
  • U.S. accusations of noncompliance against China and Russia, and
  • threats by the United States to conduct technically unnecessary, retaliatory nuclear test explosions "on an equal basis."

The situation requires a common-sense and unanimous response from all NPT states parties at this conference to:

  • reaffirm their support for the global nuclear test moratorium established by the CTBT
  • call for overdue action to secure the ratifications necessary for entry into force, and
  • call upon the nuclear weapon states to promptly engage in professional, technical talks to devise voluntary confidence building measures that can be deployed before entry into force to ensure any activities at former nuclear test sites fully comply with the CTBT's Article I prohibition on nuclear test explosions.

Article I is recognized by all of the major negotiating parties to mean that supercritical nuclear tests (which produce a self-sustaining fission chain reaction) are banned, but subcritical experiments involving fissionable nuclear material (which do not produce a self-sustaining fission chain reaction) are permitted.

To this day, the United States, China, and Russia (unlike France) all continue to actively engage in weapons-related activities at their former nuclear testing sites. Each of the three also maintain “test readiness” programs to enable them to resume nuclear explosive testing if they were to decide to abandon the CTBT and the global moratorium on nuclear explosive testing.

Although the CTBTO’s International Monitoring System is operational and far more effective than originally envisioned, very low-yield nuclear test explosions can still be difficult to detect without on-site monitoring equipment or the option to trigger short-notice on-site inspections, which the CTBTO will only be able to conduct once the Treaty enters into force.

In 2023, the head of the U.S. National Nuclear Security Administration, Jill Hruby proposed a commonsense solution to address this challenge. She suggested the United States, Russia, and China could work together and with others "to develop a regime that would allow reciprocal observation with radiation detection equipment at each other’s subcritical experiments to allow confirmation that the experiment was consistent with the CTBT."

In the absence of the CTBT’s entry into force or new voluntary confidence-building measures, there remains a risk that certain activities at these former nuclear testing sites that are prohibited -- nuclear experiments that produce a self-sustaining nuclear chain reaction -- might go undetected.

It is also possible that activities at former test sites or at other locations might be mistaken for a clandestine, very low yield nuclear test explosion, which might prompt another state to openly resume nuclear explosive testing.

This is the dangerous situation we are now facing.

Threats of Renewed Testing and Accusations of Noncompliance

On November 2, 2023, Russia cynically revoked its ratification of the CTBT, putting Russia on the same legal footing as the United States, which has yet to ratify the treaty. Russian President Vladimir Putin had previously stated that Moscow would not resume testing unless the United States did so first.

Opensource reports about construction activities at the former Chinese test site Lop Nor have raised concerns about Beijing increasing its readiness to resume nuclear weapon tests.

On October 30, 2025, U.S. President Donald Trump, threatened to resume U.S. nuclear testing "on an equal basis."

Since Trump’s initial nuclear testing comments, the White House has not been able to clarify what kind of nuclear tests Trump is talking about, and it has not offered any technical basis for his order to resume nuclear testing. The only reason appears to be political retribution: that he believes some other nuclear-armed states were testing their nuclear weapons.

Shortly after Trump initial comments, U.S. Secretary of Energy, Christopher Wright, suggested in an interview that Trump was referring to “non-critical tests” of nuclear weapons systems, probably a reference to subcritical nuclear experiments that are conducted at the Nevada National Security Site that do not involve a nuclear explosion due to a self-sustaining chain reaction. That interpretation has not yet been confirmed by the White House.

There is no technical, military, or political reason for the United States or any other nuclear weapon state to resume nuclear explosive testing. As Brandon Williams, the head of the National Nuclear Security Administration said during in a 2025 Congressional hearing: “we collected more [nuclear test] data than anyone else. And it is precisely that data that has underpinned our scientific basis for confirming the stockpile. I would not advise … testing.”

On February 6, senior U.S. officials alleged at the Conference on Disarmament that China conducted a nuclear test explosion on June 22, 2020. They also claimed that seismic data from one of the CTBTO primary seismic stations in Kazakhstan shows that China conducted a nuclear test explosion. On Feb. 17, U.S. Assistant Secretary of State Christopher Yeaw said the seismic magnitude was 2.75 and he claimed that it was produced by a 10-ton (TNT equivalent) explosion.

However, the data available from the IMS and other seismic monitoring stations in the region for that date do not indicate conclusively the seismic event was produced by a nuclear explosion, according to experts at the CTBTO and respected nongovernmental and scientific institutions.

On Feb. 6 and on Feb. 17, the CTBTO's Executive Secretary Robert Floyd issued a statement reporting that there had been two seismic events 12 seconds apart near China’s Lop Nor test site at 9:18 GMT on June 22, 2020, but that the strength of the signals was so low that “it is not possible to assess the cause of these events with confidence.”

He also reported that the CTBTO seismic station (PS23) at Makanchi, Kazakhstan suggested the locations of the June 22, 2020, seismic events were more than 100 kilometers away from the Lop Nur complex where China conducted nuclear tests in the past.

Floyd also noted the monitoring system “is capable of detecting nuclear test explosions with a yield equivalent to or greater than approximately 500 [tons] of TNT. These two events were far below that level. As a result, with this data alone, it is not possible to assess the cause of these events with confidence.”

“Mechanisms which could address smaller explosions are provided by the Treaty but can only be used once the Comprehensive Nuclear-Test-Ban Treaty enters into force. That is why it is important that the nuclear arms control framework includes the entry into force of the CTBT. The need is more urgent now than ever,” Floyd wrote. “Any nuclear test explosion, by any state, is of deepest concern,” he added.

On February 19, NORSAR, the Norwegian seismological institute, announced that it had surveyed data from seismic stations able to detect small seismic events near Lop Nor and had found only one candidate event on June 22, 2020. It estimated a seismic magnitude of 2.5-3.0, consistent with the U.S. claim.

But the NORSAR seismologists also stated: "The signal shows relatively strong compressional (P) waves compared to shear (S) waves, a feature that can be consistent with explosive sources. However, this characteristic alone is not diagnostic. Natural earthquakes can produce similar patterns, particularly when observations are limited to a single high-quality station … the data do not rule out that the event could have been a small natural earthquake…."

Similar allegations by the U.S. have also been raised towards Russia. In June 2019, during the first Trump administration, the U.S. Defense Intelligence Agency "assessed that Russia has conducted nuclear weapons tests that have created nuclear yield [in contrast] to the ‘zero yield’ nuclear weapons testing moratorium adhered to by the United States, the United Kingdom, and France.” The accusations have never specified when the alleged Russian activities may have occurred.

China and Russia have both denied the U.S. allegations.

We urge the relevant states to seek to clarify and resolve the matter in a professional manner in accordance with Article VI.C of the Comprehensive Test Ban Treaty, which provides that state parties “should, whenever possible, make every effort to clarify and resolve, among themselves or with or through the Organization, any matter which may cause concern about possible non-compliance with the basic obligations of this Treaty.”

It is important to recognize that allegations of clandestine nuclear testing absent independently verifiable data indicating a violation has occurred may be difficult to resolve.

Therefore, it is in the interest of all states not only to maintain the global moratorium on nuclear testing and advance toward CTBT entry into force, but also to develop and deploy additional tools to verify compliance prior to entry into force.

Two Nuclear Wrongs Would Not Make A Right

U.S. Assistant Secretary of State Christopher Yeaw stated on Feb. 23, that he hoped the U.S. allegations would “spur a discussion on how we all approach responsible nuclear testing behavior going forward.”

Civil society calls on every nation at this conference to make it clear that the only "responsible" nuclear testing behavior is not to do it.

Even if officials from the United States government or other governments believe that China conducted a clandestine nuclear test explosion in June 2020, or that Russia may have conducted such a test some time after 1996, two nuclear wrongs don't make a right.

Any resumption of nuclear explosive testing by China, Russia, the United States, or others would violate the "zero-yield" prohibition on nuclear test explosions established by the 1996 Comprehensive Test Ban Treaty. It would set off a chain reaction of nuclear testing worldwide that could blow apart the global nonproliferation system.

Any resumption of nuclear explosive testing would also risk producing new human suffering and environmental destruction and dishonor the longstanding struggles by impacted communities to address the ongoing, adverse health, social, environmental, and enduring consequences of these detonations and to put an end to nuclear weapons explosions once and for all.

Some U.S. officials may tell you that they think possible Chinese or Russian clandestine nuclear testing puts the United States at some kind of "intolerable disadvantage.”

This is hyperbole. The reality is that any decision to renew U.S. nuclear testing for the first time since 1992 would be militarily and technically unnecessary. Resuming U.S. nuclear explosive testing "on an equal basis" would only be an empty and counterproductive political reaction with far reaching consequences.

The U.S. nuclear weapons labs have confirmed year after year that there is no technical or military reason for the U.S. to resume testing. 

On March 26, Richard Corell, the Navy admiral who ‌commands U.S. nuclear forces, endorsed a finding by the Energy Department and Pentagon that the U.S. nuclear arsenal is safe and reliable and there is no need to conduct nuclear warhead tests. Noting that the Energy Department and Pentagon annually certify the safety and reliability ​of the U.S. nuclear arsenal, he expressed support for the most recent certification, which was issued for 2025-2026.

The United States, which has conducted some 1,054 nuclear test explosions since 1945, would learn little or nothing from additional low-yield nuclear test explosions. The same is true for Russia, which has conducted 715 nuclear tests.

According to the exhaustive 2012 study by the U.S. National Academy of Sciences on CTBT technical issues, these states “… are unlikely to be able to deploy new types of strategic nuclear weapons that fall outside the design range of their nuclear-explosion test experience without several multi-kiloton tests. Such multi-kiloton tests would likely be detectable (even with evasion measures) by appropriately resourced … national technical means and a completed IMS network.”

Conclusions

Any nuclear test explosion by any state for any reason would be a grave mistake.

We must keep the door to nuclear testing closed to preserve international peace and security, the CTBT, and the NPT.

This conference represents a critical opportunity for responsible states to rejuvenate efforts achieve entry into force of the CTBT and actively resist any move to resume nuclear testing, at any yield, for any reason, by any state.

  • We call on all NPT states parties at this conference to reiterate their collective commitment to the cessation of all nuclear-weapon-test explosions or any other nuclear explosions.
  • We call on the Conference to urge the five nuclear-armed NPT states to immediately commence technical consultations on joint mechanisms to develop new confidence building measures that strengthen capabilities to detect and deter prohibited nuclear testing prior to entry into force of the CTBT.
  • We call upon the remaining Annex 2 states to immediately commence work to achieve their ratification of the treaty.
  • We also call on all NPT states parties to acknowledge the humanitarian and environmental consequences of nuclear weapons testing and the vital importance of assisting communities affected by nuclear weapons use and testing. We call on all governments, particularly those responsible for conducting nuclear explosions in the past, to provide the necessary financial and technical support for long term environmental remediation programs, to expand access to health care especially as it relates to treatment of illnesses associated with radiation exposure, and to build independent capacity to monitor, assess, and address the environmental and health needs of the affected communities in the years to come.

Thank you for your attention.

Daryl G. Kimball, Executive Director, Arms Control Association

Mohamed AL SHAMI and Ahlam Lamrani, Alliance Internationale pour la Défense des Droits et des Libertés (AIDL)              

Peter Wilk, Administrative Chair, Back from the Brink Coalition 

Bruce J. Stedman, Back from the Brink Western Mass Hub            

Ellen E Barfield, Co-founder and Coordinator, Baltimore, Maryland USA Chapter Veterans For Peace             

Marie-Claire Graf, Co-President, Basel Peace Office*       

Andreas Nidecker, Prof. (em.) Dr. med. Radiology, M.D., Basel Peace Office Switzerland*

Oliver Meier, Head Nuclear and Multilateral Disarmament, European Leadership Network*

Joseph C. Gerson, President, Campaign for Peace, Disarmament and Common Security        

Togzhan Kassenova, Senior Fellow, Center for Policy Research, University at Albany*

Paul G. Richards, Mellon Professor of the Natural Sciences emeritus, Columbia University*

Rachel MacNair, Vice President, Consistent Life Network               

John Tierney, Executive Director, Council for a Livable World     

Hans M. Kristensen, Director Nuclear Information Project, Federation of American Scientists  

Thomas Greminger, Ambassador, Geneva Centre for Security Policy (GCSP)*

Steve Baggarly, Member, Hampton Roads Campaign to Abolish Nuclear Weapons      

Julien de Troullioud de Lanversin, Assistant Professor, Hong Kong University of Science and Technology (HKUST)*

Jean-Marie Collin, Director, ICAN France    

Sean Conner, Executive Director, International Peace Bureau (IPB)          

Michael Christ, Executive Director, International Physicians for the Prevention of Nuclear War            

Hideo, ASANO Coordinator, Japan Campaign to Abolish Nuclear Weapons       

Yerdaulet Rakhmatulla, Founder & CEO, JASA (Social Venture)*

David Cortright, Professor Emeritus, Kroc Institute for International Peace Studies, University of Notre Dame*

Deepshikha Kumari Vijh, Executive Director, Lawyers Committee on Nuclear Policy    

Susan Mirsky, Chair, Nuclear Disarmament Working Group MAPA             

Benetick Kabua Maddison, Executive Director, Marshallese Educational Initiative        

Thomas Countryman, former U.S. Assistant Secretary of State for International Security and Nonproliferation

Susan F. Burk, Former Special Representative of the President for Nuclear Nonproliferation

Tariq Rauf, Former Head of Verification and Security Policy, Alternate Head of NPT Delegation, International Atomic Energy Agency*

Aaron Tovish, Senior Advisor, NoFirstUse.Global*

Irma Argūello, Founder & Chair, NPSGLOBAL Foundation               

Patricia Marida, Coordinator, Ohio Nuclear Free Network               

Charlene Howard, Executive Director, Pax Christi USA     

Margaret Engel, Director of Policy and Outreach, Peace Action New York State                

Akira Kawasaki, Executive Committee Member, Peace Boat         

Meg Wade, Executive Director, Peace House, Ashland, OR            

Paul George, Director, Peninsula Peace and Justice Center           

John Hallam, Nuclear Disarmament Campaigner, People for Nuclear Disarmament*

Magritte Gordaneer, Director, Physicians for Social Responsibility           

Marj Plumb, DrPH, Executive Director, Physicians for Social Responsibility Maine and Texas

Victor Mizin, Leading Research Fellow, Primakov IMEMO Institute, Russia Academy of Sciences*

Lucy Duff, Member, Prince George's County MD Peace Action*

Frank N. von Hippel, Professor of Public and International Affairs emeritus, Princeton University*

Dr. Dimity Hawkins, Program Coordinator, Nuclear Truth Project

Lauren Pope, Executive Director, Rehumanize International        

Emma Claire Foley, Campaign Director, Defuse Nuclear War, RootsAction        

Paul Meyer, Adjunct Professor of International Studies, Simon Fraser University and former Canadian Ambassador for Disarmament*

Tara Drozdenko, Director of Global Security Program, Union of Concerned Scientists

Frederick K. Lamb, Research Professor of Physics and Astronomy, University of Illinois*

*Affiliation for identification purposes only

**This statement was drafted and coordinated by the Arms Control Association and the European Leadership Network

If the process of nuclear arms control is restarted, a primary challenge will be engaging China, France and the UK, along with Russia and the U.S., in limiting nuclear weapons.

June 2026
By Alexey Arbatov

The experience of six decades of nuclear arms control since the 1963 Limited Test Ban Treaty has been mostly successful, except for one aspect: the inability of Washington and Moscow to transition from their bilateral negotiating format to a multilateral format in order to physically limit and reduce nuclear arsenals beyond their two states. Over time, this has become the principal obstacle to further nuclear disarmament, at least as presented in the official positions of the two nuclear superpowers.

The P5 states—UN Security Council permanent members as well as possessors of nuclear weapons—at a 2013 news conference. They have met since 2008 to discuss strategic stability issues but never succeeded, in that forum, in limiting their nuclear arsenals. (Credit: U.S. Mission Geneva/Eric Bridiers. Accessed via Flickr. Attribution-NoDerivs 2.0 Generic)

In 2023, President Vladimir Putin suspended Russia’s participation in the last remaining major nuclear agreement, the New Strategic Arms Reduction Treaty (New START), except for continuing to observe its numerical ceilings. Among the official reasons Moscow cited were UK and French nuclear forces, which remain outside of strategic arms control. On the U.S. side, President Donald Trump in 2026 made China’s nuclear buildup the reason for ignoring Putin’s September 2025 proposal to abide by the numerical ceilings of New START for at least one year more.1 This decision did away with that treaty and ended half a century of unprecedented success with bilateral strategic arms limitation and reduction.

The termination of New START is not in itself the beginning of the disintegration of nuclear arms control, but it may trigger its final demise. In future years, during the probable impasse of strategic dialogue and continuing strategic forces modernization, there may be growing pressure within Russia and the United States to abandon the Comprehensive Test Ban Treaty (CTBT) and resume explosive nuclear tests. Such a development might finally undercut the nuclear Nonproliferation Treaty (NPT) after its predictably unsuccessful May 2026 review conference. New weapon systems being pursued by Russia, the United States, China, and other nuclear-armed states may endanger other treaties, including those banning deployment of nuclear arms in outer space (1967) and on the seabed (1971). The scariest consequence of this trend would be a chain reaction of nuclear arms proliferation around the world with the crumbling of the seven nuclear-weapon-free zones, involving 177 states, and the ensuing access to nuclear weapons by unstable states and terrorist organizations. The new nuclear world may degenerate to nuclear chaos.

Unfortunate Experience

If the process of nuclear arms control is restarted sometime in the future, one primary challenge will be engaging the three other NPT-designated nuclear-weapon states—China, France, and the United Kingdom—in the limitation of nuclear weapons. Trump has made clear that he wants China involved in any future strategic nuclear negotiations and Putin will certainly address the question of French and UK nuclear arsenals. Thus, the multilateral approach will be at the foreground of discussions, whatever other concerns the two superpowers have about space missile defense systems, tactical nuclear weapons, conventional precision guided systems, and nuclear-armed airborne and underwater autonomous vehicles.

In fact, this is not a new subject. Initially, the idea of five-party nuclear arms control talks was launched in February 2008 at the Conference on Disarmament in Geneva. After that, a number of official five-party meetings (called P5 because the five states involved are the permanent members of the UN Security Council) adopted many general declarations in support of strategic stability, ratification of the CTBT, negotiations on a fissile material cutoff treaty, indefinite extension of the NPT, and denuclearization of the Korean peninsula. As positive as those appeals were, the main goal has remained unattainable: The states did not move an inch toward practical limitation of their nuclear arms in the P5 format.2

The fundamental error of the P5 initiative was a formal interpretation of the central NPT Article VI, which obliges nuclear-armed states “to pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament.” This provision has not necessarily implied five-party arms reduction talks; it just committed all NPT nuclear-weapon states to engage in arms limitation and reduction. In fact, besides the two nuclear superpowers, France and the UK took unilateral steps to restructure and reduce their nuclear forces in 1990s and 2000s to save on defense expenditures.3 However, there were no formal agreements to ensure the strategic transparency and predictability of those steps, a point to which Putin referred while suspending New START in 2023.4

The national security policies of states define the goals of their nuclear weapon programs and disarmament stances. Of the nine nuclear nations, all except Israel (and South Africa, which abandoned its clandestine nuclear program in 1989),5 associate international prestige and status with their nuclear deterrence posture. In a more tangible way, all of them assign their nuclear forces the task of nuclear retaliation for the purpose of deterring an enemy’s aggression with nuclear and other kinds of weapons of mass destruction. The same kind of response is envisioned by France, Russia, the UK, and the United States: to deter nuclear or conventional attacks on themselves or their allies and partners.

However, the targets of nuclear deterrence are different for five of the nuclear-weapon states. For Russia, the targets are primarily the United States and U.S. allies in Europe and the Pacific. For the United States, they are Russia, China, and North Korea. For France and the UK, they are Russia. For China, the United States and India, plus Japan and South Korea, which do not possess nuclear weapons but have the capability to initiate such programs if they choose.

None of the P5 states would agree to limit its nuclear forces just for the sake of NPT Article VI if that decision does not buttress its national security. Instead, a state would have to receive in exchange an adequate limitation of military capabilities by potential opponents, foremost their nuclear forces engaged in mutual deterrence relationship. Disregarding this reality is the actual reason for the failure of the P5 dialogue.

Conditions of Arms Control Engagement

The first condition for the success of the last half century of arms control endeavors was a state of mutual nuclear deterrence. This concept was publicly recognized in the mid-1960s by the United States due to the efforts of Secretary of Defense Robert McNamara6 and adopted by the Soviet leadership under Mikhail Gorbachev in the mid-1980s.7 The second condition was the emergence of the approximate equality (parity) of strategic forces of the two superpowers in the early 1970s.

The first condition for the success of the last half century of arms control was a state of mutual deterrence, first publicly recognized by U.S. Defense Secretary Robert McNamara in the 1960s, contributor Alexey Arbatov writes. The concept was later adopted by Soviet leader Mikhail Gorbachev. (Photo from Bettman Archives)

The first condition created the material foundation of interest of the parties in limiting nuclear forces of the opponent, which created the feasibility for tradeoffs. The second provided for equal starting and ending points in negotiations because no party would be willing to legalize its inferiority or sacrifice its superiority for the sake of reaching an agreement.8

This analysis may explain the reasons of the past failures to organize multilateral nuclear arms limitation in the P5 forum. The United States, France, and UK are allies and not interested in limiting each other’s weapons. The same is true about Russia and China, which have not expressed concerns (at least officially) about each other’s nuclear forces since the late 1980s. Presently, Moscow and Beijing have nothing to gain from mutual arms reduction.

Russia’s strategic relations with France and the UK are those of mutual nuclear deterrence, but their nuclear forces are highly asymmetric providing Russia with unquestioned superiority. The two European states would not agree to legalize Russian superiority in an arms control treaty with Moscow, or to put themselves under a common ceiling with U.S. forces. This option would be unacceptable for the United States as well because it would legalize a Russian advantage of 15 percent in delivery vehicles and 30 percent in warheads, which would be seen as still more detrimental in view of the ongoing Chinese strategic forces buildup.

In U.S.-Chinese strategic relations, mutual nuclear deterrence is present, but strategic parity is absent with a huge U.S. superiority expected to persist at least for the next 10 years.9

Both China and Russia would reject putting Chinese nuclear forces under a common ceiling with the Russians. Against the background of China’s projected strategic buildup, this would imply drastic reduction of Russian forces or the stringent unilateral limitation of Chinese forces.

Reviving Arms Control

In the political domain, the most vital imperative is to prevent nuclear escalation of the Ukrainian war and facilitate the ceasefire and peaceful settlement of that conflict. Relatively less explosive, but highly desirable politically is ending the conflict in the Middle East. In the meantime, the crucial arms control priority is to sustain the CTBT and the NPT.

The end of hostilities in Ukraine would open the way to resuming at least bilateral strategic arms negotiations if leaders in Washington and Moscow genuinely recognize the value of nuclear arms control for their national security as much as their predecessors did.

Dealing with a third nuclear state through the P5 arms control process is hopeless, however nice it sounds theoretically. Instead, the United States should try harder to engage China in substantive bilateral arms control discussions. Rather than proposing agreements on “transparency” and “predictability,” Washington should make suggestions that would not legalize Chinese inferiority in the types of weapons to be subject to the accord. In addition, the United States should aim to ensure that China’s eventual strategic position is better than it would be otherwise. Due to the lack of overall parity between the two countries, an initial agreement might equally limit parts of their nuclear forces that are each other’s primary concern.

Relying on the model of the 1972 Strategic Arms Limitation Talks (SALT I) interim agreement, which put limits on selected legs of strategic triads, the nuclear forces of Russia, France, and the UK may be limited by equal ceilings. They would not legalize the superiority of any party but may alleviate security concerns of both. A joint Anglo-French position on this issue would be a useful prerequisite and might fit a concept of European nuclear deterrent.

It seems inappropriate at this moment to get deeper into technical details of possible agreements among the nuclear-armed nations. The attitude of the main nuclear states toward strategic arms control is ambiguous, and the general political environment is highly unfavorable. Suffice it is to underline that a resumption of a U.S.-Russian strategic dialogue would make it easier to achieve the participation of other nations in nuclear arms control discussions.

Even if such talks took place, difficulties implementing the outcome of any agreement would be exacerbated by the emerging “revisionist” schools in Russia and abroad, which treat six decades of nuclear arms control as the outdated vestige of the past. Today, nuclear weapons are once again being portrayed as an effective instrument of foreign policy and even practical warfighting.10 These views may tangibly affect the moods of current political elites for whom the horrors of Hiroshima and the panic of the Cuban missile crisis are no more than just ancient legends.

ENDNOTES

1. It started with the U.S. withdrawal from the Anti-Ballistic Missile Treaty in 2002 and was followed by its abandonment of the Joint Comprehensive Plan of Action with Iran in 2018, and abrogation of the Intermediate-Range Nuclear Forces Treaty (2019) and Open Skies Treaty (2020). For its part, Russia suspended participation in New START and withdrew from the Conventional Forces in Europe Treaty in 2023, retrieved its ratification of the CTBT, and refused to renew strategic arms talks in 2024.

2. That is not counting the elaboration of U.S.-Chinese strategic terms dictionary.

3. Noteworthy in the environment of unique détente during the two decades that France and the UK summarily reduced their nuclear forces from about 800 down to 510 deployed warheads. See SIPRI Yearbook 1989: Armaments, Disarmament and International Security, Oxford University Press, 1989, pp. 17-29; SIPRI Yearbook 2022: Armaments, Disarmament and International Security, Oxford University Press, 2019, pp. 369-379.

4. Vladimir Putin, “Presidential Address to Federal Assembly,” February 21, 2023.

5. Israel, like South Africa until 1989, keeps its nuclear potential in secret, although its nuclear status de-facto is well known and serves its regional influence and prestige, being at the same time a problem for nonproliferation.

6. Robert McNamara, The Essence of Security: Reflections in Office, Harper and Row (New York), pp. 51-67.

7. “Joint Soviet-United States Statement on the Summit Meeting in Geneva,” Ronald Reagan Presidential Library & Museum, November 21, 1985.

8. There were, of course, exceptions to this rule. In the SALT I interim agreement, the United States accepted Soviet advantage in the number of ballistic missiles, retaining superiority in the number of heavy bombers and MIRVed (multiple independently targetable reentry vehicle) missiles beyond the negotiated limits. In the 1987 Intermediate-Range Nuclear Forces Treaty, the Soviet Union agreed to eliminate more than twice as many missiles and three times as many warheads as the United States because the U.S. medium-range missiles posed a strategic threat to the USSR reaching deep into its territory, while the Soviet medium-range missiles were out of reach of the U.S. territory and posed only a theater threat to U.S. NATO and Pacific allies, as well as to China.

9. Compared to the U.S. total active nuclear arsenal of 3,700 warheads, China has about 600, while the ratio in strategic warheads inventory is correspondingly 3,500 to 350. See SIPRI Yearbook 2022: Armaments, Disarmament and International Security, Oxford University Press, 2025, pp. 203-209.

10. John R. Bolton, “Putin did the world a favor by suspending Russia’s participation in New START,” The Washington Post, May 4, 2023; Sergey A. Karaganov, “An Age of Wars? Article Two. What Is to Be Done,” Russia in Global Affairs, Vol. 22, No. 2, April/June 2024, pp. 5-8.


Alexey Arbatov, a leading Russian nuclear strategist, is the head of the Center for International Security at the Primakov Institute of World Economy and International Relations in Moscow.