Mohamed ElBaradei

Leading US lawmakers and the head of the International Atomic Energy Agency say a North Korean nuclear test would be a "reckless" and "cataclysmic" event.

Speaking on the CBS television program Face the Nation, Republican Senator Richard Lugar said he is concerned about reports North Korea appears to be preparing for some kind of nuclear test.

"This would be cataclysmic. This really is over the top," said Senator Lugar.

The New York Times newspaper Friday said U.S. officials are monitoring recent satellite images of North Korea that appear to show extensive preparations for a nuclear weapons test. A State Department spokesman appeared to downplay the report, saying only that U.S. officials are following the situation closely.

Senator Lugar, who chairs the Senate Foreign Relations Committee, pointed to recent comments made by the Russian ambassador to North Korea as a positive development in efforts to resolve the North Korean nuclear crisis. Ambassador Andrei Karlov called for the resumption of six-nation talks aimed at negotiating a resolution.

"There's a hopeful sign there, that the Russian ambassador weighed in finally, saying 'we think it's time for the six powers to meet again.' Now, the Russians haven't exactly been very active among the six," he added. "If they can make a contribution here that jars the Chinese sensibilities and some others, so we got down to the negotiating table again, that could be very, very helpful."

The talks include the United States, North Korea, South Korea, China, Japan and Russia. They began in August, 2003 but stalled last year after North Korea refused to return to the negotiating table. At a meeting this week in Japan, Asian and European foreign ministers strongly urged North Korea to return to negotiations without delay.

In a separate interview on CNN, International Atomic Energy Agency director-general Mohamed ElBaradei, expressed grave concern about a possible North Korean nuclear test.

"It would have disastrous political repercussions," said Mr. ElBaradei. "I am not sure how much environmental impact it could have, in terms of radiological fallout. So, I do hope that the North Koreans would absolutely reconsider such a reckless, reckless step."

Mr. ElBaradei added that any North Korean nuclear test would have what he called a regional "insecurity fallout," which would especially negatively impact Japan and South Korea. He added that, if North Korea does indeed have nuclear weapons, it would set a bad precedent for a non-proliferation regime that is already under what he described as "a good deal of stress."

Meanwhile, the IAEA head also pointed to Iran, saying the Iranian case has revealed what he termed "a serious loophole in the non-proliferation regime." He said international law allows Iran to enrich uranium for peaceful purposes. But he added that any country that has the fissile material is just a few months away from the ability to develop nuclear weapons - a margin he says may be too close for comfort.