BEIJING, China – An apparent missile test by North Korea was denounced by Washington yesterday as an attempt to bully the world as tensions over its nuclear ambitions escalated dramatically.

American officials all but confirmed Japanese media reports that the Stalinist state had tested a short-range missile from its east coast, which landed 65 miles into the Sea of Japan. The incident came days after a leading American intelligence official told the Senate that North Korea was able to arm a missile with a nuclear weapon.

With North Korea and America trading increasingly angry rhetoric, the incident cast a cloud over today’s meeting at the United Nations to review the Nuclear Nonproliferation Treaty.

The White House tried to play down alarm, suggesting that North Korea always sought to up the ante before key talks in a bid to extract concessions. “They’ve tested missiles before. This is not the first time of alleged testing,” Andrew Card, the White House chief of staff, told Fox News.

“We know what their intent is and we’re trying to keep a good, close eye on them. They’re looking to be bullies in the world.”

Talks involving America, China, Russia, South Korea, and Japan aimed at persuading North Korea to abandon its nuclear program have been stalled since last June when Pyongyang pulled out. Frustrated American officials have speculated increasingly publicly that North Korea plans an underground nuclear test next month.

President Bush last week labeled North Korea’s dictatorial leader, Kim Jong-Il, a “tyrant” and said he ran “concentration camps.”

While he said he would continue diplomatic efforts to resolve the crisis, this was some of the strongest language Mr. Bush has used of Mr. Kim and it provoked a typically florid response.

Shortly before the suspected missile test, North Korea said Mr. Bush was a “philistine whom we can never deal with … a hooligan and a world dictator whose hands are stained with the blood shed by innocent civilians.”

In 1998 North Korea startled Tokyo when it fired a long-range missile over Japan into the Pacific.

In one of the most dramatic claims yet about the North Korean threat, the head of America’s Defense Intelligence Agency said American agencies believed it had the technology for arming missiles with nuclear warheads.

Vice Admiral Lowell Jacoby told a Senate committee that North Korea was thought to have the “capability” to put a nuclear weapon on a missile, although he did not say it had done so, nor did he give any evidence.

While Mr. Bush included North Korea in his “axis of evil” in January 2002 Pyongyang has taken third place in the list of priorities. But ever since it pulled out of the Nonproliferation Treaty two years ago and expelled international inspectors, diplomats the Pentagon has warned that sooner or later the threat will have to be confronted.

The present debate is over whether Washington should keep hoping for a resumption of the six-party talks or should push for the involvement of the U.N. Security Council to try to secure a resolution imposing a de facto “quarantine” on North Korea.

Representatives of 189 nations meet at the United Nations today to tighten the Nuclear Non-Proliferation Treaty.

American officials argue that its many loopholes have aided North Korea and Iran to pursue nuclear programs. But the representatives disagree on how best to reform the treaty.