North Korea (search) presented a massive demand for energy aid Thursday at six-nation talks as Washington insisted that the North give up nuclear weapons development, Japanese news reports said.

The North wants the equivalent of 2 million kilowatts of power per year in exchange for freezing work on its nuclear program, the Kyodo News agency reported, citing diplomatic sources on the second day of talks in the Chinese capital.

It wasn't clear whether Washington would even discuss such a request, since the United States says the North must commit to dismantling the program, not just freezing development.

The United States offered its first detailed proposal for ending the dispute Wednesday, offering the North a step-by-step plan that would provide energy aid and security guarantees in exchange for the dismantling of the nuclear program.

Both Japan and South Korea say they would consider giving the North fuel oil if it freezes its nuclear program as a step toward its eventual dismantling. The United States says it wouldn't provide energy assistance under its proposal.

Also Thursday, U.S. and North Korean envoys held a rare one-on-one meeting at a Chinese government guesthouse, according to a U.S. Embassy spokeswoman, who spoke on condition of anonymity. She didn't immediately have any details of the discussions.

Competing U.S. and North Korean proposals for ending the dispute dominated the second day of talks, which also include Russia.

"There are considerable differences, but there is common ground as well," said Cho Tae-yong, a member of the South Korean delegation. He wouldn't give any details of the proposals.

North Korea was offering to freeze work at its main nuclear facility at Yongbyon (search), according to Kyodo. It didn't say whether that included a commitment sought by Washington to dismantle all nuclear facilities.

The North's energy request is the equivalent of 2.7 million tons of fuel oil per year, Kyodo said. It said North Korea is believed to consume about 8 million kilowatts per year.

U.S. officials said their proposal was meant to break the impasse in talks, which went through two earlier rounds with no major progress.

The U.S. proposal would include a three-month preparation period, in which the North would freeze work on its nuclear program, submit a list of all nuclear activities and remove key weapons ingredients.

U.S. officials said it might be several days before North Korea responded to the "very complex" proposal.

Moscow would be willing to help provide energy aid and security guarantees, said Russian envoy Alexander Alexeyev, according to the Russian news agency Itar-Tass. The report didn't say what conditions Russia might attach to that offer.

North Korea's negotiating partners all say they want an end to the communist North's nuclear weapons development.

The dispute erupted in late 2002 when Washington said North Korea admitted operating a secret nuclear program in violation of a 1994 agreement.

North Korea has agreed in principle to give up its existing weapons programs. But it denies a U.S. claim that it has a uranium-based program in addition one based on plutonium that it has acknowledged.

The U.S. government says the danger posed by the North Koreans would remain if they dismantled their plutonium program while leaving intact a uranium-based bomb program.

Washington says any settlement has to include monitoring to ensure Pyongyang doesn't renege on its promises, and must include all of the North's nuclear programs.

Ahead of the latest talks, North Korea demanded that Washington withdraw its call for an "irreversible" dismantling of its nuclear program, casting doubt on hopes for a breakthrough.

The North Korean envoy, Vice Foreign Minister Kim Gye Gwan, said Wednesday that Pyongyang was willing to renounce nuclear weapons in exchange for aid and an end to Washington's "hostile policy."

North Korea has insisted that without a security guarantee from the United States, it must keep its nuclear program to deter a possible U.S. attack.

U.S. envoy James Kelly said Wednesday that a resolution of the dispute would "open the door to a new relationship" between Washington and Pyongyang.