"We are working on a mediation proposal that asks for a concession from both U.S. President George Bush and the North Korean leader," said the chairman of Roh's transition team, Lim Chae-jung.

In recent months, Washington and Seoul have been frequently at odds over how to make North Korea give up its nuclear weapons program. Many South Koreans feel that its ally of more than half a century, the United States, is being hot-headed and risking war unnecessarily. In the mediation plan, their government would be offering to play something resembling a neutral role of go-between.

In the TV interview, Lim declined to provide details of the plan. But a senior South Korean Foreign Ministry official, Shim Yoon Joe, laid out a possible formulation during another interview broadcast on the YTN TV network: If North Korea first agrees to abandon its enriched uranium nuclear weapons program, "that can set the stage for dialogue with the United States," he said.

There was no immediate response from North Korea. U.S. officials reacted coolly to the plan, which appeared to widen the rift between the two allies just a day after President Bush denied there was any split on how to deal with North Korea.

State Department spokesman Richard Boucher stressed that South Korean statements, particularly from the Foreign Ministry, support the United States in demanding that North Korea end its nuclear programs. "I don't think there's actually been a particular offer of that sort at this point," Boucher said when asked about the South Korean proposal.

South Korea continued its diplomatic efforts Friday, sending an envoy to Moscow. The South Korean envoy conferred with officials in Beijing to urge China, North Korea's largest outside source of fuel and food, to press for a halt to the nuclear programs.

The International Atomic Energy Agency, the U.N. nuclear watchdog, is scheduled to convene an emergency meeting in Vienna on Monday to discuss its response to North Korea's decision last week to expel its inspectors. A senior administration official said that the agency is likely to issue a "last chance" warning for North Korea to cancel its program. If it does not, the issue would at some later point be referred to the U.N. Security Council.

North Korea on Friday softened the rhetoric directed at the United States. The north said that the conflict could be quickly resolved if the Bush administration agrees to enter into talks and guarantees that it will not mount an attack.

"If the U.S. legally assures us of security by concluding a nonaggression treaty, the nuclear issue on the Korean Peninsula will be easily settled," said North Korea's ambassador to China, Choe Jin Su.