Several weeks before North Korea’s surprise announcement on Friday that it would become the first country ever to pull out of the Nuclear Non-Proliferation Treaty, international inspectors showed North Korean officials American surveillance photographs and chemical evidence laying bare North Korea’s elaborate effort to deceive them about how much nuclear-bomb fuel the country has already produced.
The evidence, several diplomatic officials here said, made it clear that investigators knew that North Korea has produced plutonium from its nuclear wastes for at least three years beginning in 1989, enough time to generate enough of the material to produce one or more nuclear weapons.
“They realized that it was only a matter of time before their huge investment in this project would be shut down,” an American official said Friday. “It could not go forward with inspectors around. They felt they had no other choice.”
Nevertheless, both Japanese and South Korean officials, who have been negotiating with Pyongyang for several years about its nuclear program, said they were caught unprepared by North Korea’s decision to pull out of the treaty.
Several officials said that they view North Korea’s action as a de facto declaration that it has decided to move forward on weapons production and that the move has greatly increased tension on the Korean peninsula.
The U.S. on Friday condemned the North Korean action, and said it might ask the UN Security Council to threaten international sanctions. North Korea said it would adopt a “strong defensive countermeasure” if any sanctions are imposed.
North Korean officials traveled to Vienna the week of Feb. 22 in an effort to dissuade the International Atomic Energy Commission from conducting a “special inspection” of two sites that it said were unrelated to its atomic energy programs.
At a meeting of the agency’s board of governors that week, which the North Korean representatives attended, American surveillance photographs projected on a screen showed a Soviet-style nuclear waste dump for both liquid and solid wastes. North Korea insists the location is a military site.
American intelligence agencies are usually reluctant to show their surveillance capabilities and it was not clear whether the quality of the photographs had been degraded in some way.
The North Korean group was also shown chemical evidence drawn from samples of the small amounts of plutonium that North Korea has admitted to producing in a laboratory test in 1990. Impurities in the plutonium, officials familiar with the tests say, actually showed that it had been produced in three separate batches over three years. “They did not think we had the sophistication to detect it,” one official said.
