News Analysis: Doubts Rise on North Korea 's Uranium-Enrichment Program

As diplomats from six countries continue to hammer out the details of a Feb. 13 agreement to resolve the nuclear crisis on the Korean peninsula, questions relating to Pyongyang 's suspected uranium-enrichment program will likely play a pivotal role. U.S. officials insist that North Korea come clean about the alleged program. Verifying North Korea 's declarations, however, will be a challenge: U.S. officials recently acknowledged that their confidence in intelligence judgments about Pyongyang 's uranium capabilities has declined.

Assistant Secretary of State for East Asian and Pacific Affairs Christopher Hill told National Public Radio March 7 that resolving questions about the program will be essential to the talks' success, explaining that “we're going to have to know precisely what they've done on this before we can give them a clean bill of health.”

U.S. concerns that North Korea has been secretly pursuing such a program have played a central role in the recent nuclear crisis. Indeed, the crisis was precipitated by a U.S. decision to confront Pyongyang about those suspicions in early October 2002.

North Korea has denied that it has such a program but has said it is willing to discuss the matter. (See ACT, March 2007.)

Pyongyang is known to have a plutonium-based nuclear weapons program, but a uranium-enrichment program could provide the country with a second path to such a weapon. Gas centrifuges enrich uranium hexafluoride by spinning it at very high speeds to increase the concentration of the relevant fissile isotope. Highly enriched uranium can be used as fissile material in nuclear weapons.

According to Hill, the United States believes that “ North Korea has attempted and succeeded in buying a number of parts to put together a uranium-enrichment program.” But he added that Washington does not know how “far they got and whether they were successful in actually manufacturing highly enriched uranium.”

Similarly, a senior U.S. intelligence official confirmed in early March that Washington has become less confident than it was in October 2002 that Pyongyang is continuing to pursue an enrichment program. Ambassador Joseph DeTrani, North Korea mission manager for the Office of the Director of National Intelligence, said in a March 4 statement that all U.S. intelligence agencies “have at least moderate confidence that North Korea 's past efforts to acquire a uranium-enrichment capability continue today.”

By contrast, the U.S. intelligence community had “high confidence” in 2002 that North Korea was attempting to acquire a uranium-enrichment capability, DeTrani said, adding that the U.S. intelligence community “continues to have high confidence” that Pyongyang has pursued such a program in the past.

State of the Program

By the time the United States confronted North Korea in 2002, it had suspected for several years that Pyongyang might be pursing an enrichment program. Former Assistant Secretary of State for Nonproliferation Robert Einhorn told Arms Control Today March 21 that the United States “obtained information” at the end of the 1990s that North Korea was attempting to “obtain certain pieces of equipment that could be used in an enrichment program.” He added, however, that the “information was sketchy” as to whether Pyongyang was “actively pursuing” such a program.

However, a June 2002 National Intelligence Estimate contained “a few comments about a growing belief that North Korea had engaged in at least” a research and development enrichment project, then-Deputy Secretary of State Richard Armitage told the Senate Foreign Relations Committee in February 2003. The next month, the United States obtained intelligence that North Korea had dramatically increased its acquisition of centrifuge components, he said, adding that this information resulted in a September 2002 intelligence assessment that Pyongyang had “embarked on a production [enrichment] program.”

During a September 2006 Arms Control Association event, former Assistant Secretary of State for East Asian and Pacific Affairs James Kelly described the intelligence as “conclusive” and “retroactive in nature.” He also indicated that North Korea had possessed since about 1998 “centrifuges in very substantial numbers—way over a thousand—with associated equipment that would be necessary to run a covert centrifuge facility.”

But the administration's confidence in its knowledge of the program's scale appears to have been decreasing for some time. For example, the CIA reported in November 2002 that North Korea was “constructing a centrifuge facility” capable of producing enough fissile material for “two or more nuclear weapons per year” as soon as “mid-decade.” However, subsequent agency reports to Congress covering Pyongyang 's nuclear programs have become increasingly vague. The most recent such reports have said nothing about the program.

Likewise, a South Korean diplomat told Arms Control Today March 2 that Seoul has seen “elements” of a North Korean enrichment program, such as the importation of relevant materials, but there are “many gaps” in the government's knowledge, he added.

Most observers agree that Pyongyang has imported a significant number of centrifuge components and other enrichment-related materials. But there appears to be considerable doubt as to whether the country has an operating enrichment facility.

North Korea 's centrifuges are believed to be based on a Pakistani design, another former Department of State official told Arms Control Today March 21. Pakistani President Gen. Pervez Musharraf acknowledged last fall that a proliferation network run by former Pakistani nuclear official Abdul Qadeer Khan had provided Pyongyang with 12 to 20 complete centrifuges, as well as centrifuge designs and components. The Khan network provided two types of centrifuges, including a more-advanced centrifuge known as a P-2. (See ACT, May 2006.)

State Department officials told Arms Control Today in the fall of 2005 that North Korea likely has enough components sufficient for a “pilot” enrichment facility. A former State Department official previously told Arms Control Today that North Korea has probably imported enough components for 3,000 to 5,000 centrifuges and may have acquired enough for 6,000 to 7,000. (See ACT, October 2005.) North Korea , however, may not possess all the necessary components for an operational facility.

A State Department official told Arms Control Today last November that North Korea 's efforts to obtain materials for the program had largely stopped but pointed out that Pyongyang may have learned to produce its own components. Acknowledging that there is a “spectrum” of possibilities regarding the current state of the program, the official explained that North Korea could have an advanced enrichment program but may have halted work on it.

Whether North Korea has a facility capable of producing uranium hexafluoride is unclear. A former State Department official told Arms Control Today last October that the U.S. intelligence community does not have “evidence” that Pyongyang has such a facility.

North Korea is known to have a production line for uranium tetrafluoride, a precursor for uranium hexafluoriude, at its Yongbyon nuclear facilities. Gary Samore, who served as senior director for nonproliferation at the National Security Council during the Clinton administration, acknowledged in a March 21 interview that producing uranium hexafluoriude is relatively easy if a country is capable of producing the precursor. But he cautioned that Pyongyang 's production line may no longer be operational.

U.S. officials disclosed in 2005 an intelligence assessment that North Korea supplied Libya with uranium hexafluoride via the Khan network. (See ACT, May 2005.) But U.S. and International Atomic Energy Agency sources expressed skepticism that Pyongyang supplied the material.

Policy Decisions

Even as U.S. confidence about the suspected program has decreased, policy decisions based on those judgments have continued to reverberate.

Kelly told North Korean officials during an early October 2002 meeting that the United States had evidence that the country was pursuing a uranium-enrichment program in violation of the 1994 Agreed Framework. At the time, the United States asserted that the North Korean officials admitted to having such a program. (See ACT, December 2002.)

Under the Agreed Framework, Pyongyang froze its nuclear reactor and related facilities in exchange for the delivery of 500,000 metric tons of heavy fuel oil annually and the construction of two light-water-moderated nuclear reactors. An international consortium, the Korean Peninsula Energy Development Organization (KEDO), was charged with implementing these components of the agreement.

Although North Korea indicated it wanted to negotiate, the United States persuaded KEDO's executive board to suspend the heavy fuel oil deliveries.

Pyongyang subsequently ejected international inspectors charged with monitoring the freeze, announced its withdrawal from the nuclear Nonproliferation Treaty, restarted the reactor, and claimed to have reprocessed the spent fuel to obtain plutonium. (See ACT, November 2006.)

The belief that North Korea may have constructed an enrichment plant also apparently influenced at least some Bush administration policy decisions. A former State Department official said in a March 21 interview that some U.S. officials were “intent on making policy” based on the worst-case assumption that Pyongyang had an enrichment facility. For example, some State Department officials forcefully advocated an extremely intrusive verification scheme that would allow the United States to search for a possible North Korean enrichment facility. Several former U.S. officials have told Arms Control Today that such a plan would have been unacceptable to Pyongyang .

Former State Department Korea director David Straub, however, argued in a March 25 interview that some Bush administration officials were “intent on making policy toward North Korea based on worst-case scenarios about everything,” regardless of the enrichment issue. The entire department supported a “very intrusive inspection system, although some even more so,” he added.

A working group established by the six-party February agreement is tasked with devising a suitable scheme to verify that North Korea has complied with all of its denuclearization commitments.