N. Korea Limited Nuclear Survey

An American nuclear expert who visited North Korea’s main nuclear facility said Wednesday that he was not allowed to see enough to make a judgment on the country’s nuclear weapons capability.

Siegfried S. Hecker, former director of the Los Alamos nuclear research laboratory in New Mexico, said the North Koreans “most likely” have the ability at the Yongbyon nuclear site to make plutonium.

But, he said, he saw no convincing evidence that the North Koreans could use that metal to build a nuclear device. And even if they had that capability, he said, he saw no proof the North Koreans could convert such a device into a nuclear weapon.

Hecker added that he also was unable to substantiate a North Korean claim that 8,000 fuel rods were reprocessed last year to extract plutonium.

The nuclear scientist and several American colleagues made an unofficial visit to North Korea two weeks ago.

In testimony before the Senate Foreign Relations Committee, Hecker said the North Koreans apparently wanted to show the delegation their main nuclear site “to verify that they had taken significant actions since December 2002 and to impress us with their nuclear capabilities.” The date is when inspectors from the United Nations’ International Atomic Energy Agency were expelled from Yongbyon.

Hecker said his hosts seemed disappointed when he reported to them that he had not seen enough to draw definitive conclusions.

The Bush administration has believed for some time that North Korea has at least one nuclear weapon. It has been worried about the possibility of North Korea attempting to sell nuclear technology to terrorist groups or to what Washington calls “rogue” states.

The U.S. government neither facilitated nor discouraged the mission to North Korea. Participants have briefed administration officials.

While showing interest in the group’s conclusions, the administration has said its focus is on achieving nuclear disarmament in North Korea through a six-nation process that began last summer in Beijing.

Efforts since then to arrange a second meeting have not been successful because the parties have been unable to agree on ground rules. Besides the United States and North Korea, the nations taking part are South Korea, China, Japan and Russia.