IAEA Investigations of Iran's Nuclear Activities

Contact: Kelsey Davenport, Director for Nonproliferation Policy, (202) 463-8270 x102

The International Atomic Energy Agency (IAEA) has conducted two investigations into Iran’s past nuclear activities.

The first focused on the military dimensions of Iran’s nuclear program. The IAEA laid out its evidence and initial assessment of the possible military dimensions of Iran’s nuclear program in an annex to its November 2011 report to the agency’s Board of Governors.

The IAEA sought cooperation from Iran in clarifying the agency’s outstanding questions about the military dimensions work, but it was not until the 2015 nuclear deal, known as the Joint Comprehensive Plan of Action, required Iran to cooperate with the agency’s investigation prior to implementation of that accord, that Tehran provided the IAEA with enough information for the agency to issue a final assessment.

The IAEA’s December 2015 report concluded that Iran conducted a “range of activities relevant to the development of a nuclear explosive device were conducted in Iran prior to the end of 2003 as a coordinated effort, and some activities took place after 2003.” The report further assessed that there were “no credible indications” of activities relevant to weaponization after 2009 or any diversion of nuclear materials for military purposes. Following the report, the IAEA’s Board of Governors passed a resolution in December 2015 closing the military dimensions investigation.

The IAEA’s second investigation began in 2018 and is focused on evidence suggesting that Iran failed to declare all nuclear materials and activities from its pre-2003 nuclear program as legally required by its safeguards agreement. As part of the investigation, the IAEA visited three undeclared locations in 2019 and 2020. Environmental samples indicated that processed uranium had been present at all three sites. Iran has yet to provide the IAEA with technically credible explanations for the presence of uranium at those locations. The IAEA was investigating a fourth location, but said it had no more questions for Iran after assessing in a May 2022 report that Tehran should have declared to the agency activities related to uranium metal that took place at the site. While this safeguards investigation is separate from the JCPOA, Iranian President Ebrahim Raisi said in August 2022 that the Iran will not return to compliance with the JCPOA until the IAEA’s investigation is closed.

• Military Dimensions Investigation (2011-2015)
• Safeguards Investigation (2018-present)

In November 2011, the IAEA released a report with an annex outlining the agency’s evidence that Iran had engaged in various activities related to nuclear weapons development. The report provided evidence suggesting that Iran pursued a structured nuclear program before the fall of 2003, and that certain weapons-related activities continued after that program was dismantled.

In that report, the IAEA divided its questions and concerns into 12 areas: 1) nuclear program management structure, 2) procurement activities, 3) nuclear material acquisition, 4) possession of nuclear components for an explosive device, 5) detonator development, 6) high explosives and associated experiments, 7) hydrodynamic experiments, 8) relevant modeling and calculations, 9) development of a neutron initiator, 10) preparations to conduct a nuclear explosive test, 11) integration of a nuclear warhead into a missile, and 12) studies looking into a prototype Iranian re-entry vehicle

Additionally, Iran was found to have acquired nuclear weapons development information and documentation from an unnamed clandestine nuclear supply network and to have explored development of an indigenously-designed nuclear weapon. The IAEA’s published November 2011 report omits details about the latter two points, but the nuclear supply network is widely believed to have been that of Pakistani physicist A.Q. Khan.

The report, consistent with a 2007 U.S. intelligence assessment, speculates that Iran’s structured nuclear program (known as the AMAD Plan) “was stopped rather abruptly pursuant to a ‘halt order’ instruction issued in late 2003 by senior Iranian officials,” and that certain research and development activities may have resumed. For more on the IAEA’s November 2011 report, see: The IAEA’s Iran Report: Assessment and Implications.

The agency’s 35-member Board of Governors adopted a resolution Nov. 18, 2011, that expressed “deep and increasing concern about the unresolved issues regarding the Iranian nuclear program” and called on Iran to provide the agency with “access to all relevant information, documentation, sites, material, and personnel.”

The IAEA sought answers from Iran regarding concerns raised in the 2011 report, but there was little progress until Iran and the IAEA reached the Framework for Cooperation in November 2013. The full text of the initial Framework for Cooperation and its accompanying annex is available here.

Under the Framework for Cooperation, Iran and the IAEA committed to resolving the agency's concerns through a step-by-step process. An annex to the framework laid out the first six actions that Iran pledged to take within three months.

On February 9, 2014, Iran and the IAEA announced a further seven actions that Iran would take by May 15, 2014. Iran completed the initial two sets of actions within the time period specified.

A May 20, 2014 meeting resulted in an agreement on an additional 5 actions to be taken by August 25, 2014. Iran completed three of the five actions by the end of August 2014. Two remaining issues related to nuclear weapons development remained unresolved. Iran and the IAEA met several times throughout the spring, and in its May 29, 2015, quarterly report, the IAEA noted that Iran shared information on one of the outstanding issues related to nuclear weapons development. Before all of these actions were completed, this agreement was superseded by a July 2015 agreement that ultimately led to closure of the investigation. 

2015 Roadmap for the Clarification of Past and Present Outstanding Issues Regarding Iran’s Nuclear Program

On July 14, 2015, Iran and IAEA announced they reached an agreement to address the agency’s outstanding questions. The agreement, known as the Roadmap for the Clarification of Past and Present Outstanding Issues Regarding Iran’s Nuclear Program, laid out a schedule for Iran to address the IAEA’s concerns and the agency to complete its investigation.

The IAEA announced on August 15, 2015, that Iran met the first deadline for providing documents and written explanations to the agency's questions regarding the 12 main areas for investigation as outlined in the November 2011 annex. The agency submitted follow-up questions to Iran on September 9, and on September 20, IAEA Director General Yukiya Amano and Deputy Director General Tero Varjoranta traveled to Tehran to discuss the investigation and visit the Parchin site. They confirmed that environmental samples were taken at Parchin for analysis in IAEA labs. On October 15, 2015, the deadline for additional responses, the IAEA confirmed that Iran had responded to its follow-up questions and completed all activities under the roadmap.

The completed assessment, released on December 2, 2015, concluded that Iran had pursued a nuclear weapons program prior to 2003, including a coordinated “range of activities relevant to the development of a nuclear explosive device,” but did not divert nuclear material from its civilian nuclear program as part of its weaponization efforts.

The report found that although Tehran’s organized nuclear weapons program ended in 2003, some activities continued through 2009. According to the assessment, the “activities did not advance beyond feasibility and scientific studies, and the acquisition of certain relevant technical competencies and capabilities.” The agency said it found “no credible indications” that nuclear material was diverted to the weapons program or that any undeclared activities have taken place since 2009.

In several areas, like nuclear testing preparations and fuzing, arming, and firing a payload, the IAEA did not receive any new information. In other areas, such as Iran’s work at a uranium mine, the IAEA assessed that Tehran’s activities were consistent with its declaration to the IAEA. However, the IAEA assessed that Iran’s program structure, computer modeling of a nuclear explosive device, and certain types of experiments with detonators were part of a nuclear weapons development program prior to 2003.

Mark Toner, a deputy spokesman at the U.S. Department of State, said on December 2 that the IAEA’s conclusion is “consistent with what the United States has long assessed with high confidence.”

Following a meeting on December 15, 2015, the 35-member IAEA Board of Governors voted unanimously to close the investigation into Iran's past weaponization work while continuing to report on Iran's implementation of the July 2015 nuclear deal with the P5+1.

Iran's ambassador to the IAEA Reza Najafi said that Iran "disagreed" with some of the agency's findings, arguing that the “scientific studies of dual-use technologies have always been for peaceful civilian or conventional military uses” rather than nuclear weapons work, he said.

The full text of the "road-map for the clarification of past and present outstanding issues regarding Iran’s nuclear program" is available here. Highlights of the IAEA's findings in each of the 12 areas are below:

1. Program management structure: The IAEA assessed that, prior to 2003, Iran had an organized structure “suitable for the coordination of a range of activities relevant” to nuclear weapons design. The activities that continued beyond 2003 were not a coordinated program. 
    
2. Procurement activities: The IAEA had “indications” that Tehran attempted to purchase items relevant to developing a nuclear weapon prior to 2007 and information that Iran purchased materials for its fuel cycle activities through companies not affiliated with the Atomic Energy Organization of Iran. Iran admitted to looking into procuring a high-speed camera for conventional purposes but said it ultimately did not do so. 
    
3. Nuclear material acquisition: The IAEA assessed that the Gchine uranium mine, previously thought to be a potential source of uranium for undeclared nuclear activities between 2000-2003, would not have produced any substantial amounts of nuclear material before 2006. The IAEA found that the activities at the mine were consistent with Iran’s explanations and declarations. Overall, the IAEA assessed that “any quantity of nuclear material” that would have been available for the nuclear weapons development program “would have been within the uncertainties associated with nuclear material accountancy and related measurements.” 
    
4. Nuclear components for an explosive device: The IAEA had evidence that Tehran had access to documentation on the conversion of uranium compounds to uranium metal, which is part of the weaponization process, and made progress on reducing a uranium compound into a metal form. Tehran denied that it conducted any metallurgical work for weapons purposes. The IAEA’s final assessment found no indication of Iran conducting activities related to the uranium metal document. 
    
5. Detonator development: The IAEA assessed that Iran’s work on explosive bridge wire detonators has “characteristics relevant to a nuclear explosive device.” The agency found that some of Iran’s explanations, that the detonators were developed as a safer alternative because of explosive accidents, were “inconsistent” and “unrelated” to the IAEA’s timeframe for detonator development. 
    
6. Initiation of high explosives and associated experiments: Iran admitted to the IAEA in August and September 2015 that it conducted work on certain types of explosives, but had a “technical requirement for the development” of multipoint initiation explosive technology for conventional weaponry. The IAEA noted that there are non-nuclear weapons applications for the development, but assessed that the work was “relevant to a nuclear explosive device.” 
    
7. Hydrodynamic experiments: As part of its investigation over the past several months, IAEA officials were able to visit Parchin, a military site where the agency suspected that Tehran conducted hydrodynamic tests in an explosive chamber. Since the IAEA requested access in 2012, Iran conducted extensive construction and renovations. Tehran said in September 2015 discussions with the IAEA that one of the main buildings in question was used for storing chemicals for the production of explosives. An environmental sampling at the site found “chemically man-made particles of uranium” but did not indicate that it was used for long-term storage of chemicals as Iran claimed. The IAEA assessed that its satellite imagery analysis and environmental sampling “does not support Iran’s statements on the purpose of the building” and that Iran’s activities at the site impeded the agency’s investigation. The IAEA did not draw a definite assessment as to what occurred at Parchin. 
    
8. Modeling and calculations: The IAEA assessed that Iran conducted modeling and calculations related to nuclear explosive configurations prior to 2004 and between 2005-2009. During the agency’s investigation between August-October 2015, Iran maintained that it was not in a position to discuss its work on hydrodynamic modeling because it was for conventional military purposes and not an IAEA concern. The IAEA noted in its report that there are conventional applications for such modeling and that the calculations derived from the modeling were incomplete and fragmented, but assessed overall that Iran conducted computer modeling of a nuclear explosive device between 2005-2009. 
    
9. Neutron initiator: The IAEA’s evidence indicated that Iran continued work on neutron initiators after 2004, although the agency assessed prior to the July 2015 agreement with Iran that some of the indicators that Iran undertook work on generating neutrons through shock-compression were “weaker than previously considered.” Iran provided the IAEA with information about its neutron research and let the IAEA visit a research intuition in October 2015. Iran maintained that its research in the area was not related to “shock-driven neutron sources.” 
    
10. Conducting a test: The IAEA noted it has not received any additional information regarding Tehran's plans to conduct a nuclear test since its November 2011 report. The IAEA noted in the November 2011 report that Iran may have undertaken “preparatory experimentation” relevant to a nuclear weapons explosive device and obtained a document on the safety arrangements for explosive nuclear testing. 
     
11. Integration into a missile delivery vehicle: The IAEA assessed that two of the workshops it identified in 2011 as producing components and mock-up parts for engineering of a Shahab-3 (Iran’s medium-range ballistic missile) re-entry vehicle for a nuclear warhead exist and that the capabilities are “consistent with those described” in documentation provided to the agency on Tehran’s work on a re-entry vehicle. 
     
12. Fuzing, arming, and firing system: The IAEA report noted in the Final Assessment report that it had not received any new information since the November 2011 report on development of a prototype firing system for a Shahab-3 payload that would allow the missile’s payload to safely re-enter the atmosphere and then explode above a target or upon impact.

Safeguards Investigation (2018-present)

Overview

In 2018, the IAEA began to investigate evidence that Iran failed to declare all of its nuclear materials and activities as legally required under its safeguards agreement with the agency. Since June 2020, the IAEA has provided regular, quarterly reports to the agency’s Board of Governors regarding the investigation, which focuses on four locations in Iran where evidence suggests Tehran conducted undeclared nuclear activities prior to 2003 and stored equipment and materials from that period. The IAEA visited three of the undeclared locations in 2019 and 2020 and samples taken from the sites indicated the presence of processed uranium. Iran has not provided technically credible explanations for the presence of uranium at the sites, even after reaching an agreement with the IAEA in March 2022 on a process for addressing the agencies inquiries. The IAEA concluded in a May 2022 report that activities related to uranium metal at the fourth site should have been declared to the IAEA.

The IAEA Board passed three resolutions, in June 2020, June 2022, and November 2022, urging Iran to fully cooperate with the agency’s investigation. In August 2022, Iranian officials insisted that text be added to the draft agreement to restore the JCPOA noting that Iran wants the IAEA’s investigation to be closed prior to reimplementation of the deal.

Background

The agency’s safeguards investigation began after Israel stole documents pertaining to Tehran’s past nuclear weapons program from Iran earlier that year and shared the so-called “Atomic Archive” with the agency. Then Israeli Prime Minister Benjamin Netanyahu also publicly pressed the IAEA to investigate a warehouse in the Turkazabad district of Iran during a speech to the UN General Assembly in September 2018.

While the IAEA has not publicly discussed the archive, IAEA officials have reiterated that any information provided by member states is subject to the agency’s review and verification process. Additionally, then U.S. Under Secretary of State for Arms Control and International Security Andrea Thompson confirmed in March 2019 that the IAEA was evaluating the archival materials.

In November 2019, Acting-Director General Cornel Feruta told a special convening of the Agency’s Board of Governors that the IAEA had “detected natural uranium particles of anthropogenic origin at a location in Iran not declared to the Agency.” It was later confirmed that location was the Turquzabad site, which IAEA inspectors had visited earlier that year to take environmental samples.

Seeking to explain the presence of undeclared uranium, Iranian officials have stated that the warehouse was previously owned by a private company that may have used the facility to store equipment from Iran’s uranium mine. The Atomic Energy Organization of Iran suggested that the presence of uranium was due to contamination from the equiptment.

In March 2020, the IAEA released a report detailing efforts by the Agency over the past year to investigate an additional three sites in Iran for evidence of undeclared nuclear materials and activities. The report noted that the IAEA requested access to two of the sites in January 2020, but Iran had refused to allow inspectors to visit the areas in question.

In June 2020, the IAEA Board of Governors adopted a resolution calling on Iran to fully implement its comprehensive safeguards agreement and cooperate with the Agency. In August 2020, Iran and the IAEA reached an agreement allowing the agency to visit two sites to conduct environmental sampling. It was reported Sept. 30, 2020, that the IAEA completed its inspections of both locations, and that environmental samples were sent to agency labs to test for the presence of nuclear material. The samples confirmed the presence of processed uranium at the two additional sites.

In March 2022, Iran and the IAEA reached agreement on a process for concluding the agency’s investigation by the June 2022 IAEA Board of Governors meeting. However, IAEA Director General Rafael Mariano Grossi said in a May 30, 2022 report that Tehran failed to provide technically credible explanations for the presence of uranium at the three locations. Following the report, the IAEA’s Board of Governors passed a resolution censuring Iran for its failure to cooperate and urging the Tehran to provide credible answers to the IAEA’s inquiries. In the May 30 report, the IAEA noted that it had no further questions about one of the four locations. The IAEA assessed that Iran undertook activities related to uranium metal at the site that should have been declared to the agency under Iran’s safeguards agreement.

After the IAEA Board passed its resolution in June, Iran did not engage with the agency on the investigation until September, but raised the issue of the investigation during negotiations to restore the JCPOA and pushed for the investigation to be closed as part of that agreement and commitment from the IAEA not to engage in further investigations into Iran's past nuclear work. 

On September 26, 2022, IAEA Director General Rafael Mariano Grossi said that he met with Atomic Energy Organization of Iran head Mohammad Elsami in Vienna to resume talks on the safeguards investigation. He said there is "a lot of work" ahead to close the investigation. 

The IAEA Board of Governors passes a third resolution on Nov. 17, 2022 censuring Iran for failing to cooperate with the agency's safeguards investigation. The resolution "decides" it is urgentand essential for Iran to cooperate with the agency's inquiries. In a statement introducing the resolution, the E3 and the United States said that "last-minute promises from Iran to hold additional meetings in the future, after years of delay and denial, are late and inadequate." The four countries said Iran "must fulfill its safegaurds obligations" and that the issues are "not historical" but integral to verifying Iran's declarations. 

An IAEA team traveled to Iran Dec. 18-19 to continue discussions on the safeguards probe, but did not announce any further steps or actions to advance the investigation. 

The Four Locations

In its regular quarterly reports to the IAEA Board of Governors, the IAEA has provided details about its preliminary conclusions as to the nuclear activities that occurred at each location. In May 2022, the IAEA identified the locations under investigation. The following is a summary of the IAEA’s evidence and preliminary assessments of the undeclared activities at each location. Additional information is available in the May 2022 IAEA report.

Location 1: Turquzabad

Information available to the IAEA suggests that Iran used the Turquzabad site, previously referred to in agency reports as Location 1, to store nuclear material and equipment, including containers transferred from Varamin (location 3). In January 2019, the IAEA requested that Iran clarify whether the site was used for such purposes. Iran told the IAEA there were no undeclared materials or activities at the location. In February 2019, IAEA inspectors then requested information from Iran about the movement of containers from the site that the agency observed using satellite imagery and requested access to the location. Environmental samples taken indicated the presence of processed uranium.

Iran’s initial responses to the IAEA regarding the presence of the processed uranium were not deemed technically credible. As a result of the March 2022 agreement between the IAEA and Iran, Tehran provided further explanation for the presence of the uranium, saying that there was “the possibility of an act of sabotage by a third party to contaminate the area.” Iran provided no evidence to support that claim, according to the May 2022 IAEA report. Iran also said it could not identify where containers removed from site in 2018 are currently located. The May 2022 IAEA report concluded that the presence of uranium particles at the site “is not clarified.”

Location 2: Lavisan-Shian

The IAEA investigated evidence of an undeclared uranium metal disc that had undergone drilling and processing at Lavisan-Shian, previously identified as Location 2. As part of its investigation, the IAEA visited a declared facility in Iran where uranium metal discs had been produced but was unable to determine if the Lavisan-Shian disc was at that site. The IAEA informed Iran in January 2022 that it “could not exclude that the disc had been melted, recast and was not part of the declared nuclear material inventory.” In its May 2022 report, the IAEA assessed that the activities at Lavisan-Shian “were not declared by Iran to the Agency as required under the Safeguards Agreement.” The IAEA also said it has no further questions about this location.

Location 3: Varamin

Information and evidence available to the IAEA suggests that Iran used Varamin for storing nuclear materials and/or fuel-cycle-related activities. The IAEA’s evidence suggests that materials and equipment from the site were moved to Location 1, Turquazabad, for storage.

The IAEA requested access to Varamin in January 2020, but Tehran denied the request. Inspectors were able to access the site after Iran and the agency reached an agreement in August 2020 and environmental samples confirmed the presence of uranium at the location. The IAEA ask Iran to provide clarifications about the presence of uranium, which Tehran has failed to credibly answer.

In the May 2022 report, the IAEA noted that Iran stated in March 2022 that the location was used for the production of sodium sulphate. The IAEA stated that this explanation does not match the satellite imagery taken from the site and the results of the environmental samples that were collected during an August 2020 visit to the site. Furthermore, it does not explain the presence of the uranium particles. The IAEA reported that Iran offered the additional explanation of third-party sabotage to contaminate the area but provided no evidence to support that claim. In the report, the IAEA offers its assessment of Varamin, that it was an “undeclared pilot-scale facility for the processing and milling of uranium ore and conversion into uranium oxide” and possible UF4 and UF6 at laboratory scale from 1999-2003.

Location 4: Marivan

Informational available to the IAEA suggests that Iran intended to use nuclear materials at Marivan. The IAEA reported that safeguards relevant information suggests that Iran conducted “explosive experiments with protective shielding in preparation for the use of neutron detectors” at one of the areas under investigation at Marivan, previously referred to as Location 4 by the IAEA.

The IAEA requested access to the site in January 2020, which Tehran denied. Inspectors were later able to visit the location and take environmental samples as part of the August 2020 agreement between the agency and Iran. In January 2021, the IAEA requested clarification from Iran regarding the presence of processed uranium found at the site.

In August 2021, Iran provided the agency with some documentation about Marivan and said that one of the areas in question was built to support a mine managed by another IAEA member state until it was abandoned in 1994 and that the bunkers at the site were used for deactivating munitions. The IAEA assessed that some of this documentation was inconsistent with its evidence. As part of the process initiated by the March 2022 process, Iran informed the IAEA that it had never produced the type of material found at the site and that the presence might be accounted for by an act of third party sabotage to contaminate the site. Iran, however, provided no evidence for this claim. During the consultations, Iran also said that some of the photographs of the bunkers were fabricated. The IAEA said in its May 30 report that the presence of the uranium “is not clarified.”