China and the United States remain committed to expanding their "effective coordination" to resolve the North Korean nuclear standoff and reduce tensions over other regional hot issues, a senior Chinese diplomat said Friday.

China has been keen to restart the long-stalled multilateral talks aimed at ending the North's nuclear weapons program, but South Korea and the U.S. insist that a new round of six-party talks will not take place unless North Korea demonstrates its seriousness about denuclearization through concrete actions.

"With regard to regional issues like the DPRK (North Korea) nuclear issue, Iran, Syria and Afghanistan, China and the U.S. are working hard to expand and deepen the convergence of interests, while maintaining effective coordination," Chinese Assistant Foreign Minister Zheng Zeguang told a forum on U.S.-China relations.

"As the prominent members of the U.N. Security Council, in terms of promoting the solutions for regional hotspot issues and promoting global peace and stability, the opportunities for the U.S.-China cooperation are actually increasingly not decreasing," Zheng said.

After conducting its third nuclear test early this year, North Korea has repeatedly expressed its desire to resume the six-party talks, but has made no signs of giving up its nuclear weapons program. This week, South Korea's spy agency confirmed that the North has restarted a 5-megawatt plutonium reactor in a move that may give Pyongyang more fissile fuel to make bombs.

However, in a recent informal meeting in Berlin, Germany, with former American officials, North Korea's chief nuclear envoy, Ri Yong-ho, was quoted as saying that Pyongyang was ready to put a moratorium on its nuclear testing, one of a string of preconditions set by Seoul and Pyongyang to restart the six-party talks, said Joel Wit, a former U.S. State Department official who attended the Berlin meeting, told Yonhap News Agency on Wednesday.

South Korea and the U.S. also called on North Korea to freeze production of plutonium and uranium, put a moratorium on the test-launching of long-range rockets and allow international nuclear inspectors back into the North.

The off-and-on six-party talks that involve the two Koreas, China, the U.S., Japan and Russia have been stalled since late 2008. North Korea has conducted three nuclear tests since 2006.

Persistent territorial and maritime disputes between China and its neighbors, including Japan and the Philippines, have worsened as of late, and have become a major geopolitical headache for the U.S., which recently declared that it was making a strategic "pivot" to Asia.

During the forum, Zheng repeated China's stance that the U.S. should stay away from the disputes.

"The East China Sea and the South China Sea issues and other sovereignty disputes are very sensitive issues that should be properly resolved bilaterally by china and other relevant countries," Zheng said.

"We hope that the U.S. sees clearly what is right and what is wrong and take an objective and fair position and guard against trouble-making by relevant countries," Zheng said.

Stephen Hadley, who served as a national security adviser for former U.S. President George W. Bush, urged both Washington and Beijing to forge better coordination to deal with these challenges.

"Neither the U.S. nor China can solve these problems alone," Hadley told the forum.

"It means that China and the U.S. should work together on an equal footing with the rest of the international community to address and begin to deal with these global challenges," he said. (Yonhap News)