The first indication that preparations for the talks could be in trouble came hours after top State Department official John Bolton warned Pyongyang should not seek to stall the meeting expected around December 17 or 19.

Asked whether Bolton was hinting there was already a hitch in the dialogue, another US official said on condition of anonymity: "He did not make any mention of the talks taking place in December.

Asked whether the meeting was more likely to happen in January or February, the official replied: "Yes."

The State Department earlier refused to be drawn into firming up the date of the talks, which most reports have said could come after the second week of December.

"That date has been put out there, but we haven't given it any special credence," said deputy spokesman Adam Ereli.

"We are hopeful that a second round can be convened soon, but aren't able to be more specific than that."

Deputy Secretary of State Richard Armitage earlier said that despite hopes for a resolution of the crisis, the showdown with North Korea remained a "messy situation" that was "damn dangerous."

"We believe that we have an agreement to have another six-party talk in Beijing, probably in December, but not definitely.

"As long as all the six parties to the problem are willing to talk about it, I think we're in a situation where eventually we can bring it to resolution. But it's damn dangerous."

It was not clear which issue was complicating the ballet of diplomacy orchestrated by China designed to launch the talks under before the end of this year.

Most discussion in recent days has focused on a US-proposed written security guarantee which would be in exchange for a North Korean promise to give up nuclear weapons.

Washington has pushed for an intrusive verification regime, which may prove unpalatable to North Korea, already blamed by the Bush administration for junking a previous anti-nuclear pact signed in 1994.

Bolton's remarks followed a warning by North Korea that Japan was not qualified to take part in the six-nation talks because it wanted to raise abductions of its citizens by North Korean agents.

He said in a speech that though the US side hoped to make progress on ending the 13 month-old crisis, it was determined that North Korea would win no reward for "bad behavior."

"Attempts to delay or postpone the six-party talks simply because one or more of the parties wishes to raise issues of vital concern should be rejected," said Bolton, once branded "human scum" by North Korea for his hawkish views on the country.

"Japan for example feels strongly that it should have the right at least to raise the issue of North Korean abductions of Japanese citizens over the years," said Bolton, under secretary of state for arms control and international security.

"For Japan, this is a fundamental issue, and Japan's desire to raise it should be respected. Japan's participation in the six-party talks is essential."

Pyongyang's official media said Japan had "abducted and forcibly drafted" millions of Koreans during its 1910-1945 colonial rule over the Korean peninsula.

"Pretending not to know about this hard fact it is vociferating about the abduction of a few Japanese in a bid to poke its nose into the talks and create a complication there," the Korean Central News Agency (KCNA) said.

"This behavior has deprived Japan of any qualification to be a trustworthy dialogue partner."

Japan accuses North Korea of abducting Japanese nationals in the 1970s and 1980s and defied Pyongyang by bringing up the case at the first round of six-way talks in Beijing in August.

China, which has been coordinating diplomacy leading up to the second round of six-nation talks said Tuesday that no dates had yet been set.

Several parties in the discussions have however indicated that the talks, involving the United States, Japan, South Korea, China, Russia and North Korea, could take place in Beijing around December 17 or 19.

The State Department said Tuesday that its North Korea pointman, James Kelly, would meet counterparts from South Korea and Japan later this week to refine strategy for the talks.

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