Expectations of any concrete outcome were low as delegates from the United States, China, the two Koreas, Japan and Russia began discussions at 9 am (0100 GMT) at the Diaoyutai Guest House in the western part of the capital.

"I don't think that they, particularly the Americans and the North Koreans, will be able to narrow the gap," said Wu Guoguang, an international relations scholar at the Chinese University of Hong Kong.

While the talks were held behind closed doors with minimal media access, it appeared that the US and North Koreans were simply too far apart on fundamental issues.

According to reports in the Japanese media, Kim Jong Il, North Korea's reclusive dictator, told Chinese leaders during a recent visit to Beijing that he would not give up the peaceful use of nuclear energy.

North Korea has also made clear that even if it is to abandon its attempt to build nuclear bombs -- a program whose existence has not been definitively proven -- it will want some kind of reward.

The US government, meanwhile, has insisted that North Korea give up its nuclear program without the promise of any immediate quid pro quo.

"It's in North Korea's best interest to embrace the opportunities provided by the six-party talks," a US embassy official said.

However, South Korea's Yonhap news agency cited reports that the US and Japanese delegates, meeting Tuesday ahead of the working level talks, supported a South Korean offer of energy aid to North Korea.

That would be in return for freezing the nuclear program as a first step toward complete dismantling, according to Yonhap.

The US delegation, headed by former CIA officer Joseph DeTrani and including representatives from the National Security Council and the Pentagon, met all other teams apart from the North Koreans Tuesday, the US embassy said.

The working-group talks are the first since a second round of high-level six-party meetings ended inconclusively in Beijing in late February.

This week's discussions could help prepare the ground for a third round of high-level six-way negotiations expected to take place in the Chinese capital before the end of June.

Reflecting the low hopes of speedy outcomes, analysts said the mere fact that talks were going on was a mark of progress.

"The six delegations can use the occasion to communicate with each other about what happened in the past several weeks," said Wu.

"I don't think they can reach any agreement that they can announce."

On the eve of the Beijing talks, North Korea said it would regard any sanctions imposed by Japan against the communist country as a "declaration of war" and would punish Tokyo with prompt counter-measures.

Pyongyang's official Korean Central News Agency Tuesday urged Japan to think twice about the "disastrous consequences" that would follow such action.

Japan is considering new laws to ban port calls by certain ships in a move aimed largely at preventing visits by North Korean vessels.

Japanese lawmakers have also been weighing economic sanctions against Pyongyang following public anger over North Korea's abduction of Japanese nationals in the 1970s and 1980s.

WAR.WIRE