Assistant Secretary of State Christopher Hill answers reporter's question during a press briefing in Seoul, Friday

A senior U.S. envoy has wrapped up a diplomatic mission to Asia saying a sense of urgency is growing about the North Korean nuclear crisis. The comments come a day after President Bush urged international consensus in dealing with what he called North Korea's "dangerous" leader.

Assistant Secretary of State Christopher Hill says there is no hard deadline, but puts the blame squarely on North Korea for delaying the resumption of talks.

"The fundamental issue is that North Korea still has not made, really, its strategic decision to do away with its weapons," he said. "Obviously the situation grows with a sense of urgency because it's now been some ten months and counting that we've last had a session."

Mr. Hill briefed reporters in Seoul Friday, after spending the week consulting with senior officials in South Korea, Japan, and China, which together with Russia and the United States, are party to the stalled talks.

Since last June, when it boycotted talks, North Korea has said it possesses nuclear weapons and plans to make more, despite having signed several agreements to remain nuclear free.

Mr. Hill called it "disquieting" that North Korea's Yongbyon nuclear reactor had not been functioning for about three weeks - a sign the North may be reprocessing spent fuel into weapons material. He urged Pyongyang not to conduct a nuclear test.

"To go ahead and have a nuclear test at a time when the six-party talks are in abeyance, I think, would be extremely troubling," he said.

On Thursday, the head of the U.S. Defense Intelligence Agency told U.S. lawmakers he believes North Korea is capable of mounting a nuclear warhead on a missile. If correct, that would mean North Korea could target its regional neighbors or even the western United States.

In a press conference Thursday evening, President Bush referred to North Korean leader Kim Jong Il as a "tyrant", and said it was best to assume the intelligence estimate about the North's missile capability is correct.