The UN nuclear watchdog confirmed in a confidential report on Thursday that South Korea enriched a tiny amount of uranium in 2000 to a level close to what would be useable in an atomic weapon.  

A senior diplomat close to the International Atomic Energy Agency (IAEA) also said a senior government scientist, the president of the Korean Atomic Energy Research Institute in Taejon, South Korea, had authorized the experiments with the uranium and knew about work with plutonium, also useable in nuclear weapons.

South Korea's government has said it had no knowledge of plutonium and uranium experiments, though the IAEA said it was still trying to verify this.

"Although the quantities of nuclear material involved have not been significant, the nature of the activities -- uranium enrichment and plutonium separation -- and the failures by (South Korea) to report these activities in a timely matter ... is a matter of serious concern," said the report.

"The Agency is continuing the process of verifying the correctness and completeness of (South Korea's) declarations," it added.

The report said the IAEA had found no indications the South Korean experiments had gone beyond small-scale laboratory activities. Seoul has repeatedly stated that it had no ambitions to develop nuclear weapons.

South Korea also denied that any bomb-grade uranium had been found. But the IAEA confirmed the scientists had enriched a small amount of uranium to 77 percent uranium-235, the atom needed in large quantities in weapons. Bombs with uranium fuel usually have cores enriched to at least 80 to 90 percent.

But the average enrichment for the 10 experiments was only around 10 percent uranium-235.

"The ROK (Republic of Korea) stated that only about 200 mg of enriched uranium were produced, following which the experiments were terminated and the installations where these experiments had been carried out had been dismantled," the report said.

The IAEA said that the scientists had produced 0.7 grams of plutonium.

A country would need 15 to 25 kg of weapons-grade uranium or around seven to 10 kg of plutonium for the core of a weapon.

Repeated refusals

The IAEA praised South Korea for its "active cooperation" but said that it still needed detailed documentation of the uranium enrichment and plutonium separation activities in order to complete its investigation.

However, the IAEA said that South Korea had refused repeated requests to take samples at some of its nuclear facilities. Seoul did not acknowledge its plutonium separation experiment, conducted in 1982, until March 2003 despite repeated questioning by the IAEA about plutonium particles found at sites.

Some diplomats in Vienna say South Korea's concealment of its plutonium and uranium experiments were a violation of Seoul's obligations under the nuclear Non-Proliferation Treaty (NPT), which could require the IAEA board of governors to refer the matter to the UN Security Council.

Seoul has been lobbying diplomats in Vienna, where the IAEA is based, not to refer the matter to the Security Council. However, diplomats said that Washington believes the council should take up the issue as a precedent for similar violations by Iran.

The IAEA board will discuss Iran and South Korea on Nov. 25.

(Chinadaily.com.cn via agencies, November 12, 2004)