"The resumption of the talks is in the interest of all parties, and of course that includes North Korea," foreign ministry spokesman Kong Quan told a regular press briefing.

"We think all sides should make more efforts, to show goodwill, flexibility and sincerity," he said. "But the key thing is that the main parties, North Korea and the United States, should make greater efforts."

The comments came as Chinese envoy Wang Jiarui returned from Pyongyang where North Korean leader Kim Jong-Il said he was willing to return to the six-party talks, under the right conditions.

Less than two weeks ago, North Korea announced it had developed nuclear weapons and would pull out of the negotiations that also include China, South Korea, Japan and Russia.

China has brokered three rounds of six-party talks. However, North Korea snubbed a fourth round last September, citing Washington's "hostile policy" and accusing it of trying to topple its government.

Asked when he thought the talks could resume, Kong said: "That isn't an issue that we should put too much emphasis on at the moment. We need an active and flexible attitude ... and to show patience on solving the problem."