At the same time, the State Department warned North Korea that Washington placed little stock in its denials to two unofficial US delegations that it had a program to develop highly enriched uranium in violation of a 1994 agreement.

"We are very hopeful that we will soon have a continuation of six-party talks but we don't have any date at this time," said James Kelly, the top US diplomat for Asia and the Pacific.

Kelly, who met with senior Japanese and South Korean officials to discuss the situation, said he believed it was still possible to hold a second round of talks that would eventually result in North Korea's agreeing to the dismantlement of its nuclear programs.

"This is possible and we are very hopeful that this will be developed as we continue the six-party talks," he told reporters.

Such an agreement, however, would have to be comprehensive and include verifiable pledges by Pyongyang to eliminate its uranium enrichment program, plutonium reprocessing and existing atomic weapons, he said.

North Korea showed the unofficial US delegations what it said was plutonium but denied having enriching uranium, rejecting US accounts of a 2002 meeting in which Pyongyang was said to have admitted such a program.

That reported admission set off a diplomatic tidal wave, and sent both sides deep into their worst crises in years with North Korea kicking out UN arms inspectors, unfreezing its plutonium program and pulling out of the nuclear Non-Proliferation Treaty.

Kelly, the head of the US delegation at the 2002 meeting said he had no doubt North Korea had made the admission despite Pyongyang's insistence to the unofficial US teams that Washington had misinterpreted its statements.

"I remain convinced by that conversation that a uranium enrichment program was admitted," he said, adding, however, that US intelligence information had confirmed its existence before the admission was made.

"We weren't asking for such an admission and it was surprising only in terms of tactics," Kelly said. "This is information that we are very strongly convinced about."

A member of one of the unofficial US delegations testified before Congress on Wednesday that North Korea likely had the capacity to make weapons grade plutonium but had not proved it had already made or could develop nuclear bombs.

Kelly downplayed the significance of what the North Koreans had told or shown the delegations, suggesting that it was far more important to return to the six-party talks which include host China, Japan, the two Koreas, Russia and the United States.

"This is interesting but we hope it doesn't distract or delay the process of getting to the serious work among the several countries to get to resolving the nuclear weapons programs," he said.

After Kelly spoke, deputy State Department spokesman Adam Ereli said progress was being made toward a resumption of the talks -- the first round of which ended inconclusively last year -- but would provide no details.

"We are not seeing, I would say, stasis or setbacks," he told reporters. "At the same time, we have not yet reached the point where we can announce that there are going to be talks."

WAR.WIRE