North Korea today expressed willingness to return to six-nation nuclear disarmament negotiations it quit six months ago, but only after it talks directly to the United States to improve hostile relations.<br/>North Korea's official news agency reported that Leader Kim Jong-Il gave the commitment at a meeting yesterday with visiting Chinese Premier Wen Jiabao.<br/>Highlighting the urgency of the issue, a South Korean source said the North appeared to be in the final stages of restoring plutonium-producing plants that it had shut down before abandoning the six-party process.<br/><br/>