WASHINGTON – The United States on Friday condemned North Korea’s decision to quit a treaty considered the cornerstone of global efforts to curb the spread of nuclear weapons.

“North Korea has thumbed its nose at the international community,” said Secretary of State Colin Powell, speaking alongside Mohamed ElBaradei, director general of the International Atomic Energy Agency.

Ultimately, Powell said, the U.N. Security Council must take up North Korea’s pursuit of nuclear weapons and shirking of international obligations. “It is a very serious situation,” Powell said. “We are not going to be intimidated. We are not going to be put in a panic situation. We are going to work this deliberately.”

At the same time, Powell renewed the Bush administration’s overture to hold direct talks with North Korea and said, “We hope the North Korean leadership will understand the folly of its actions.”

ElBaradei also took a hard line, accusing North Korea of “a policy of defiance.” He said unless North Korea reversed its actions within a few weeks the Security Council should intervene.

Overseas, Britain, France, Russia, Germany and Sweden also denounced the North Korean decision. Japan called on its regional neighbor to reverse course.

President Bush talked by telephone with Chinese President Jiang Zemin. Bush’s spokesman, Ari Fleischer, said the president told Jiang, “This binds us in common purpose.”

Bush also told the Chinese leader the United States seeks a peaceful solution to the standoff, while Jiang “reiterated China’s commitment to a non-nuclear Korean peninsula,” Fleischer said.

Meanwhile, two North Korean envoys met in Santa Fe, N.M., with Gov. Bill Richardson, a former U.N. ambassador and diplomatic troubleshooter. Richardson said they met for a total of seven hours Thursday and Friday, and planned a working dinner Friday night. They will resume talks Saturday before the North Koreans depart.

Richardson — who stressed he is not an official envoy of the Bush administration — said the talks covered a range of issues, but he would not give details. He said he has been in frequent contact with Powell.

“I support the administration’s policy,” he said. “I think it is a sound policy. The administration, through Secretary Powell, has conveyed to me some strong views and I have conveyed them to the North Koreans.”

He added: “I’m out of the foreign policy business. I’m governor of New Mexico … but I believe that to resolve problems you’ve got to talk.”

Powell said he would not offer an assessment until the talks were concluded.

A senior U.S. official said before talks ended Friday that the North Korean diplomats had expressed an interest in dialogue with the United States but had “nothing particularly new” to say to Richardson.

On Monday, the U.N. atomic agency criticized North Korea for removing cameras and other devices that were helpful in monitoring its nuclear programs. But it gave North Korea a last chance to cooperate with international inspections.

The decision by North Korea to quit the treaty followed on Friday.

The U.N. Security Council could punish Pyongyang with worldwide economic sanctions, further deepening its economic crisis.

North Korea’s envoy to China hinted that his government would consider reversing its decision if the United States, Japan and South Korea resume fuel shipments.

The Bush administration has ruled out concessions but said otherwise there were no restrictions on talks.

South Korea’s ambassador to Washington, Sung Chul Yang, said “Dialogue doesn’t mean yielding to their nuclear brinkmanship. Dialogue is to find out what they have in mind.”

“Any military flare-up over North Korea having nuclear weapons is a life-and-death scenario,” he said in a National Journal interview.

Daryl Kimball, executive director of the private Arms Control Association, said North Korea’s unfreezing of its plutonium plants and its withdrawal from the treaty were dangerous.

“However,” Kimball said, “the United States must pursue a a policy of engagement that produces better results than its failed policy of righteous name-calling.”

ElBaradei said Pyongyang’s withdrawal from the pact was “a very dangerous precedent” that could contribute to instability on the Korean Peninsula. “Defiance will not achieve its stated objective,” he said.

Rep. Doug Bereuter, R-Neb., a member of the House Intelligence and International Relations committees, said he did not object to negotiations with North Korea, but “we cannot fall into the cycle of extortion we’ve fallen into over a period of years.”

North Korea said it was withdrawing instantly from the treaty, which was signed by 180 countries, but not by India and Pakistan, which have nuclear weapons.

State Department spokesman Richard Boucher said North Korea was required by the treaty to give 90 days’ notice, and that its suspension from the accord in 1993 could not be applied to meet that provision.

The Nuclear Non-Proliferation Treaty permits five countries, the United States, Britain, France, China and Russia, to retain their nuclear weapons but seeks to limit the “nuclear club” by discouraging the spread of nuclear technology.

The effect of abandoning the treaty would be to stop the International Atomic Energy Agency from monitoring North Korea’s programs.