The North Korean government on Friday expressed willingness to compromise with the United States about ending its nuclear weapons programs, saying it would "show flexibility" if U.S. officials improved their offer of energy aid from South Korea and agreed to provide some assistance itself.

In an unusually mild statement read by a North Korean official as six-nation talks in Beijing neared a close, North Korea emphasized it might be willing not only to freeze "all facilities related to nuclear weapons" but also to dismantle them. The North Korean government also refrained from publicly berating the United States as it had during the past two rounds of the talks.

But U.S. officials here said North Korean negotiators continued to deny the existence of a secret uranium enrichment program that the Bush administration and its allies insist must be disclosed and dismantled as part of any deal. One senior U.S. official described the two sides as "far from agreement."

"There's some good, some bad, some a little ugly, but not as much as has been the case in the past. The results would have to be described as mixed so far," said the U.S. official, who briefed reporters on condition of anonymity. "There are no breakthroughs." During the talks, the Bush administration presented a more specific proposal for resolving the 21-month standoff, offering North Korea the possibility of energy aid from South Korea, security assurances and other benefits during a three-month test period if it promised to disclose and end its nuclear weapons programs.

North Korean delegates on Friday described the proposal as "constructive," the same language they used the day before, and told the U.S. negotiating team that the proposal "was being very carefully studied in Pyongyang," the U.S. official said. Officials expect the talks to end Saturday with a plan to continue discussions at a working-group level.

In exchange for a freeze of its nuclear programs, North Korea wants the United States to remove it from a list of terrorist nations and lift economic sanctions, the North Korean statement said. The North Korean government also asked in the statement that the United States "participate in providing" it with a 2000-megawatt energy capability, about the same amount that would have been generated by two light-water reactors the United States and its allies had promised to build for the Pyongyang government in a deal that fell apart in 2002.

"Compensation is a necessary element of creating trust," the North's statement said, adding that its freeze would begin once the compensation was delivered. But the statement also said that if the United States agreed to take part in providing energy aid, North Korea was "willing to show flexibility" about its demands on the sanctions and the terrorism list. The U.S. proposal envisions South Korea and perhaps other countries providing the North with heavy fuel oil at the start of its freeze, but the United States would not provide energy aid until after North Korea began dismantling its nuclear programs.

The North also said in the statement that its freeze would cover "all facilities related to nuclear weapons," including nuclear materials that have already been reprocessed, and that it would pledge not to build, test or transfer nuclear weapons. "What we are saying is that we will not only freeze these facilities, but if the conditions are met, we'll dismantle these facilities," it said.

North Korean negotiators made a similar declaration during the talks, and they specified that the offer included a key facility in Yongbyon that the North has said produces plutonium for use in bombs, according to the U.S. officials.

The U.S. officials described the statements as helpful, but said that North Korea was still not clear in describing what other facilities, programs and materials are covered by its proposal and that it has not provided many details about how it would dismantle its programs as opposed to simply freezing them.

A major problem, they said, is that the North continues to deny operating a secret uranium enrichment program. The current crisis began in October 2002 after the U.S. government confronted North Korea with evidence of the program, which violated a 1994 agreement to freeze its nuclear activities in exchange for oil and other aid. At the time, the Bush administration says, North Korea admitted it had a uranium program.

In its statement, North Korea appeared to suggest that its government had had difficulty reaching a consensus to offer a freeze, saying it "required a large political commitment."

On Thursday, North Korea's chief envoy said in a private session with U.S. negotiators that some people in his country want to test a nuclear weapon and might do so, apparently referring to military hard-liners, U.S. officials said. "It was not phrased as a threat," said the senior U.S. official, but "we made clear that we would certainly not welcome any such thing and that any such thing would be a very unwise choice."