US envoy says six-party talks won't resume

Talks among six nations to get North Korea to abandon its nuclear programs in return for aid and other concessions won't resume while Pyongyang works on a new uranium enrichment facility, a U.S. envoy said Tuesday.

The new facility came to light over the weekend after North Korea showed it to a visiting American nuclear scientist, claiming that the highly sophisticated operation had 2,000 completed centrifuges. Top U.S. military officials warn that it could speed the North's ability to make and deliver viable nuclear weapons.

The U.S. special envoy on North Korea, Stephen Bosworth, ruled out any resumption of the stalled six-party talks among the U.S., China, Russia, Japan, South Korea and North Korea while that program continues. The talks were started in 2003 in efforts to coax Pyongyang to give up its nuclear ambitions.

"Needless to say, we regard this development with great seriousness," he told reporters at a Tokyo hotel. "We do not contemplate resuming negotiations while active programs are under way or while there is a possibility that North Koreans would test another nuclear device or test a missile."

Bosworth met in Tokyo with Japanese Foreign Minister Seiji Maehara during the second stop of an Asian tour that also included South Korea. He was scheduled to fly later Tuesday to China.

"We are consulting with our partners in the six-party process," Bosworth said. "We are committed to moving forward in very close coordination with our partners, particularly of course with our allies, the government of Japan and the government of South Korea."

American scientist Siegfried Hecker reported over the weekend that during a recent trip to the North's main Yongbyon atomic complex, he was taken to a small, industrial-scale uranium enrichment facility.

Hecker, a former director of the U.S. Los Alamos National Laboratory who is regularly given glimpses of the North's secretive nuclear program, said the North Korean program had been built in secret and with remarkable speed.

In Washington, officials said Monday the facility could be nothing more than a "publicity stunt," trying to calm fears while not playing down the seriousness of the problem.

White House press secretary Robert Gibbs called on the North to return to the six-party talks.

"We do not wish to talk simply for the sake of talking," Gibbs said. "The North Koreans have to be serious about living up to their obligations."