Allegations of a North Korean uranium enrichment program date as far back as 1993. The program, however, has been shrouded in secrecy, with only limited information available in the public domain. The U.S. government has suspected a possible enrichment program at least since 1998, with the State Department and the CIA levying increasingly strong accusations until 2002, only to subsequently back down. Subsequent information has been unclear, although signs in 2007 and 2008 appeared to indicate that North Korea at a minimum had pursued a limited highly enriched uranium program.

Throughout 2009, North Korea made increasingly explicit threats to begin an industrial uranium enrichment program, ostensibly to supply a yet-to-be-built light water nuclear power plant, and claimed to have successfully completed the necessary experiments to proceed. The predominant concern with Pyongyang having a uranium enrichment programs is that it can be extremely difficult to determine whether the program is geared toward producing reactor fuel or weapons-grade uranium.

North Korea is known to possess a pool-type ITR-2000 research reactor partially fueled by uranium enriched to 80 percent—below the desired enrichment for nuclear weapons, but potentially useful as a shortcut to producing weapons-grade uranium. One estimate placed the amount of this uranium in the reactor at 42 kg.[1] This fuel was supplied by the Soviet Union beginning in 1987, however, and supply was not continued by the Russian Federation after the Soviet collapse. There is no indication that this uranium has been diverted from its intended use.

References to an early North Korean uranium enrichment program are generally vague or difficult to verify. Russia's Foreign Intelligence Service (SVR) made passing reference to two uranium mines and two enrichment plants in an October 1993 report.[2] Subsequent disclosures have neither supported nor disproved this report. South Korean media entities have occasionally made similar allegations, ranging from tentative suggestions to sensationalist accusations. In 2003, the high-level North Korean defector Hwang Jang-yop spoke of a 1996 agreement with Pakistan for the purchase of enrichment equipment.[3] Hwang's claims appeared to be validated by later events, particularly as more details surfaced regarding A.Q. Khan's interactions with North Korea.

U.S. President Bill Clinton began raising the issue of Pakistani supply of enrichment equipment and technology to North Korea in 1998 with Pakistani President Pervez Musharraf.[4] President Musharraf, in his memoirs, ultimately confirmed that such assistance had occurred, and that it included 'nearly two dozen P-1 and P-2 centrifuges,' specialized equipment such as a flow meter and oils, and training in Pakistani facilities.[5]

While intelligence in late 1998 and 1999 indicated that North Korea had attempted to purchase equipment which could potentially be used for enrichment, such as specialized electrical frequency converters,[6] it was unclear at the time if North Korea was actively pursuing a uranium enrichment program.[7]

In 2001, the Central Intelligence Agency publicly disclosed that North Korea was 'seeking centrifuge-related materials in large quantities to support a uranium enrichment program,' along with 'equipment suitable for use in uranium feed and withdrawal systems' which are key to supplying enrichment facilities.[8] Later, in 2002, it cited 'clear evidence' of work on a centrifuge facility and concluded that North Korea appeared to be working towards 'a plant that could produce enough weapons grade uranium for two or more nuclear weapons per year when fully operational.'[9]

In October 2002, in response to accusations made during the visit of a U.S. delegation to North Korea, Vice Foreign Minister Kang Suk-joo reportedly conceded the existence of a uranium enrichment program to Assistant Secretary of State James Kelly.[10] North Korean officials, however, subsequently denied the disclosure. In 2003, the CIA dropped public references to a North Korean uranium enrichment program, which may have been the result of a North Korean freeze on enrichment activities after the revelation of their discovery, or alternatively, because past intelligence was determined to be inaccurate. Beginning in 2007, however, assessments by the Office of the Director of National Intelligence began to cite again the past pursuit of a uranium enrichment capability and raised concerns that North Korea could potentially be continuing a covert program.

Concerns have been exacerbated by the discovery of enriched uranium particles on aluminum tubes provided by North Korea in 2007,[11] as well highly enriched uranium particles on North Korean documents in 2008.[12] Both the tubes and the documents were provided as confidence-building measures, but have served to intensify suspicions instead. While there are alternate explanations—for example, cross-contamination from Pakistani equipment or North Korea's research reactor—the plausibility of these is debatable.

North Korea is currently known to possess a small number of centrifuges purchased from A.Q. Khan's laboratories in Pakistan, and components for thousands more.[13] North Korea may have continued to operate a small-scale test program, but likely has not attempted large-scale enrichment. There are doubts that North Korea has the ability to supply a serious enrichment program; key elements of the enrichment cycle, such as a uranium hexafluoride production facility, are still not known to exist on an industrial scale in North Korea.[14]

Nevertheless, following the breakdown in relations brought about by a long-range ballistic missile test in April 2009, and further worsened by a second nuclear test in May 2009, North Korea has declared its intention to build a light-water nuclear power plant with the necessary enrichment facilities to provide its own fuel through a series of four progressively confrontational pronouncements. These statements have led to serious concerns that the plant will provide the pretext for a large-scale enrichment program which could be used to produce uranium for weapons systems.[15] The most recent declaration, dated 13 June 2009, reads: 'The process of uranium enrichment will be commenced. Pursuant to the decision to build its own light-water reactor, enough success has been made in developing uranium enrichment technology to provide nuclear fuel to allow the experimental procedure.'[16] This announcement came less than two months after North Korea declared it would 'start the technological development for ensuring self-production of nuclear fuel.'[17] The short period between the two statements, far too brief for a serious experimental program to have begun and concluded, lends credence to already plausible accusations of a previous small-scale covert enrichment program.

It would take a substantial investment to construct an enrichment facility capable of supplying a light-water nuclear power plant. Furthermore, a power plant would require a vast support structure, which would further delay the process. The nuclear power plant could be used as a justification, however, for smaller-scale enrichment activities before a full-scale program begins. This raises serious concerns, as a much lower amount of enrichment capacity is necessary to produce enough HEU for a nuclear weapon.

Sources:
[1] 'Summary Tables and Charts' in 'Global Stocks of Nuclear Explosive Materials,' Institute for Science and International Security, 7 September 2005, www.isis-online.org/ global_ stocks/ end2003/ summary_ global_ stocks.pdf.
[2] SVR, 'Weapons of Mass Destruction in the World' (Russian text), Russian Foreign Intelligence Service website, October 1993, svr.gov.ru/ material/ 2-1.html.
[3] Kim Min-cheol, 'Hwang Tells of Secret Nuke Program,' Chosun Ilbo, 4 July 2003, english.chosun.com/ site/ data/ html_ dir/ 2003/ 07/ 04/ 2003070461016.html.
[4] Larry A. Niksch, 'The Assessments and Evidence Before Bush, Chosun Ilbo, 20 March 2005, english.chosun.com/ w21data/ html/ news/ 200503/ 200503200025.html
[5] Pervez Musharraf, In the Line of Fire (New York: Free Press, 2006), p. 296.
[6] Hui Zhang, 'Assessing North Korea's Uranium Enrichment Capabilities,' Bulletin of Atomic Scientists, 18 June 2009, www.thebulletin.org/ web-edition/ features/ assessing- north- koreas- uranium- enrichment- capabilities.
[7] Paul Kerr, 'News Analysis: Doubts Rise on North Korea's Uranium-Enrichment Program,' Arms Control Today, April 2007, www.armscontrol.org/ act/ 2007_04/ NewsAnalysis.
[8] CIA, Unclassified Report to Congress on the Acquisition of Technology Relating to Weapons of Mass Destruction and Advanced Conventional Munitions, 1 July through 31 December 2001, CIA Archive: Recurring Reports, www.cia.gov/ library/ reports/ archived- reports- 1/index.html.
[9] Ibid; and CIA, Unclassified Report to Congress on the Acquisition of Technology Relating to Weapons of Mass Destruction and Advanced Conventional Munitions1 July through 31 December 2002, CIA Archive: Recurring Reports, www.cia.gov/ library/ reports/ archived- reports- 1/index.html.
[10] James Kelly, briefing on Recent Developments in the Asia Pacific region, Foreign Press Centers Archive, Washington, D.C., 19 November 2002, 2002-2009-fpc.state.gov/ 15308.htm.
[11] Glenn Kessler, 'Uranium Traces Found on N. Korean Tubes,' Washington Post, 21 December 2007, www.washingtonpost.com/ wp-dyn/ content/ article/ 2007/ 12/20/ AR2007122002196.html.
[12] Glenn Kessler, 'New Data Found On North Korea's Nuclear Capacity,' Washington Post, 21 June 2008, www.washingtonpost.com/ wp-dyn/ content/ article/ 2008/06/20/ AR2008062002499.html.
[13] Paul Kerr, 'Questions Surround NK Uranium Program, Arms Control Today, October 2005, www.armscontrol.org/ print/ 1905.
[14] Ibid.
[15] 'DPRK Foreign Ministry Vehemently Refutes UNSC's 'Presidential Statement,'' KCNA, 14 April 2009, www.kcna.co.jp/ item/ 2009/ 200904/ news14/ 20090414-24ee.html; 'UNSC Urged to Retract Anti-DPRK Steps,' KCNA, 29 April 2009, www.kcna.co.jp/ item/ 2009/ 200904/ news29/ 20090429-14ee.html; 'DPRK Permanent Representative Sends Letter to President of UNSC,' KCNA, 4 September 2009, www.kcna.co.jp/ item/ 2009/ 200909/ news04/ 20090904-04ee.html; 'DPRK Foreign Ministry Declares Strong Counter-Measures against UNSC's 'Resolution 1874,'' KCNA, 13 June 2009, www.kcna.co.jp/ item/ 2009/ 200906/ news13/ 20090613-10ee.html.
[16] 'DPRK Foreign Ministry Declares Strong Counter-Measures against UNSC's 'Resolution 1874.''
[17] 'UNSC Urged to Retract Anti-DPRK Steps.'

	Updated October 2009