North Korea has agreed to push towards a third round of international talks on the region's nuclear crisis, Chinese Foreign Minister Li Zhaoxing has said.
North Korea says it has reprocessed thousands of spent nuclear fuel rods
He was speaking after visiting Pyongyang - the first such visit by a Chinese foreign minister in five years.
Speaking in Beijing on his return, Mr Li said his talks with the North Korean leader, Kim Jong-il, had taken place in "a happy atmosphere".
Correspondents say China is seen as the key mediator in the nuclear standoff.
"My impression is that the North Korean side holds a positive attitude," Mr Li told reporters.
He said his trip had been "very smooth, very enjoyable, very successful".
North Korea and the US are locked in confrontation over Pyongyang's nuclear weapons programme.
A second round of six-nation aimed at resolving the crisis ended in Beijing in February without a final agreement.
But the countries involved in the talks - China, the two Koreas, Japan, Russia, and the US - agreed to set up lower-level working groups to resolve specific problems before further high-level talks, due in June.
The nuclear crisis was sparked in October 2002 when US officials said North Korea had admitted to having a secret uranium-based nuclear programme, in violation of a 1994 agreement.
It has since restarted a mothballed nuclear power station, thrown out United Nations nuclear inspectors and pulled out of the Nuclear Non-proliferation Treaty.
North Korea says it has reprocessed thousands of spent nuclear fuel rods at the Yongbyon nuclear facility, from which extracted plutonium can be used to manufacture nuclear bombs.
The US insists that Pyongyang must dismantle its nuclear facilities. But Pyongyang says it will only do so in return for economic and energy aid, and security guarantees from Washington.