David Kyd, a spokesman for the International Atomic Energy Agency (IAEA), said the spent fuel is in a cooling tank monitored by two agency inspectors. There was no sign that the North Koreans had any immediate plans to take away the material, but he added: 'Weeks or months - that is a different matter.' It is estimated that after reprocessing, the spent fuel could yield enough plutonium for three or four nuclear weapons.
Of more immediate concern, however, is that the inspectors have been prevented from taking samples to determine how much plutonium has been diverted in the past. The North Koreans admit to having produced a small amount, but the IAEA has evidence that more is being concealed - enough, it is believed, for one or two nuclear devices.
'That historical record is now lost,' a Western diplomat said yesterday. 'There is no way of reconstructing it. North Korea has violated the nuclear Non-Proliferation Treaty, and the only question now is how we react.'
Apart from extinguishing any hope that Kim Il Sung's unpredictable Stalinist regime might finally comply with the treaty to the satisfaction of the IAEA, the unsupervised discharge of the reactor has made it clear that Pyongyang will proceed with its nuclear programme whatever the inducements on offer. Last year the United States held two rounds of direct talks with North Korea in which it offered help to rescue the country's collapsing economy and held out the possibility of diplomatic recognition if the North would stop trying to develop nuclear weapons.
'They were offered a perfectly decent fall-back,' said the diplomat, 'but they chose to sacrifice a third round of talks which was virtually within their grasp. The US was prepared to meet nearly all their conditions, but instead they chose to de-fuel.' Some American analysts have argued that North Korea sees its nuclear programme as a cheap form of insurance against reunification with South Korea, which will remain effective no matter how far it falls behind the South in terms of economic or military strength.
Pyongyang's open defiance of the IAEA, making it impossible to check what it has done in the past, means there is no specific deadline for action. Disagreement among the five permanent members of the United Nations Security Council means it may not discuss the matter for several more days.
China, North Korea's closest ally, has prevented its Security Council partners from passing any resolution on the last couple of occasions the question has been debated. All it has been prepared to allow is a statement by the president of the council, urging the North Koreans to comply with the Non-Proliferation Treaty. 'It would be a jump for the Chinese to agree to a resolution, and a further jump to agree to sanctions,' said the Western diplomat.
Peking has given next to no sign of dropping its traditional opposition to sanctions in almost any circumstances, but the US, Britain and France are pressing ahead with drawing up proposals for their staged imposition on North Korea. The first round might include action to curb Pyongyang's exports of conventional weapons and cutting air links. Preventing imports of oil and food, which nearly all go through China, would not be proposed until later. Nor is is it clear when Japan would be asked to stop all remittances from North Korean residents, worth about dollars 600m ( pounds 400m) a year.
Nobody was under any illusions that sanctions would be very effective, said the diplomat, 'but it is a question of credibility. The Western members have reached the conclusion that the Security Council cannot take this lying down.'
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