In a reversion to its well-worn brinkmanship tactics, the foreign ministry in Pyongyang blamed Washington for the 16-month nuclear impasse and warned the talks starting Wednesday without US flexibility.

"If the US insists on putting forward fictitious calls on a highly-enriched uranium program, and condemning North Korea, this will only result in the prolonging of the nuclear question," Xinhua quoted a North Korean foreign ministry spokesman as saying.

"If the United States administration had not put forward a hostile policy against North Korea, naming it as a part of the 'Axis of Evil', and broken the October 1994 DPRK-US Agreed Framework, then the present nuclear problem would never have emerged."

The crisis began in October 2002 when Washington said North Korea had admitted running a clandestine nuclear weapons program based on enriched uranium in violation of the 1994 nuclear freeze accord.

The spokesman said the freezing of its plutonium-based nuclear program, which it first offered to do in December, would only happen once the issue of compensation was resolved.

"If in this round of talks it is put forward to 'first freeze then compensate' North Korea will resolutely oppose it," he said.

"This will mean that the talks have been paralysed and this is not good for any of the parties."

Washington has long insisted on agreement from North Korea for a complete and verifiable dismantling of its weapons programs before it offers the economic and energy aid and security guarantees that Pyongyang wants.

This includes an acknowledgement from Pyongyang that it not only has a plutonium-based program but also a uranium-based one.

On Monday, however, the US appeared to soften its stance, indicating a willingness to consider a freeze as a first step in the dismantling process.

China, North Korea's closest ally, admitted Tuesday there would be no quick fix to the lingering standoff.

"The North Korea nuclear issue is a complicated process of solution seeking. It will be a long and drawn out process," foreign ministry spokesman Zhang Qiyue said.

North Korea's chief delegate to the talks Deputy Foreign Minister Kim Kye-gwan arrived in Beijing Tuesday and went straight into meetings with Chinese officials.

With all six parties -- North Korea, South Korea, United States, Japan, Russia along with China -- now in Beijing, a series of bilateral meetings were held Tuesday, including one-on-ones between China and North Korea and China and the United States.

In an effort to defuse the tension, South Korea's chief negotiator Lee Soo-Hyuck will hold a meeting with North Korea's Kim later Tuesday to lay out a three-stage proposal for ending the showdown.

Lee, who held a final strategy session Monday in Seoul with US envoy James Kelly and Japanese delegate Mitoji Yabunaka, said he would also present the positions of these two countries in the meeting.

In the first phase in the proposal, North Korea is to declare it intends to abandon all nuclear weapons programs, while the other participants in the talks will promise to provide a security guarantee.

In the second phase, North Korea is to freeze its nuclear facilities and to return to the nuclear Non-Proliferation Treaty and accept inspections of the United Nations' International Atomic Energy Agency (IAEA).

South Korea, Russia and China will provide energy and heavy fuel oil in return.

In the third phase, North Korea will complete the elimination of its nuclear programs and the United States will give a written security guarantee to the isolated country.

WAR.WIRE