MOSCOW (AP)  North Korea vowed Tuesday to restart its nuclear reactor and to boycott international disarmament talks for good in retaliation for the U.N. Security Council's condemnation of its rocket launch. Russia, voicing regret over the move, urged Pyongyang to return to the negotiating table. The Foreign Ministry called the U.N. statement "legitimate and well-balanced," and Foreign Minister Sergey Lavrov said all sides must stick to the current disarmament process. China, the North's main ally, appealed for calm. In Washington, a senior U.S. official called the decision "unfortunate." "It will further isolate the North from the rest of the international community, and the North will have to deal with that," the official said, speaking on condition of anonymity. North Korea's denunciation of the council's "hostile" move came just hours after all 15 members, including Beijing and Moscow, unanimously agreed to condemn the April 5 launch as a violation of U.N. resolutions and to tighten sanctions against the regime. The U.N. statement, issued eight days after the launch, was weaker than the resolution Japan and the United States had pursued but still drew an angry response from Pyongyang, which called it "unjust" and a violation of international law. North Korea claims it sent a communications satellite into space as part of a peaceful bid to develop its space program. The United States and others call the launch an illicit test of the technology used to fire an intercontinental ballistic missile, even one eventually destined for the United States. A Security Council resolution passed in 2006, days after North Korea carried out an underground nuclear test, prohibits Pyongyang from engaging in any ballistic missile-related activity — including launching rockets that use the same delivery technology as missiles mounted with warheads, Washington and other nations say. The council on Monday demanded an end to the rocket launches and said it will expand sanctions against the communist nation. The council also called for quick resumption of disarmament talks. President Obama called the statement a "clear and united message" that North Korea's action was unlawful and would result in real consequences, White House spokesman Robert Gibbs said. North Korea, following through on earlier threats to withdraw from international disarmament talks if the council so much as criticized the launch, announced Tuesday it would boycott the negotiations hosted by China. "The six-party talks have lost the meaning of their existence, never to recover," the North's Foreign Ministry said in a statement, declaring it would never participate in the talks again and is no longer bound to previous agreements. Since 2003, envoys from six nations — the two Koreas, the United States, China, Russia and Japan — have been meeting in Beijing for sporadic negotiations on getting Pyongyang to give up its nuclear program in exchange for aid and other concessions. Under a 2007 six-party deal, North Korea agreed to disable its main nuclear complex in Yongbyon, north of Pyongyang — a key step toward dismantlement — in return for 1 million tons of fuel oil and other concessions. Disablement began later that year. In June 2008, North Korea famously blew up the cooling tower at Yongbyon in a dramatic show of its commitment to denuclearization. But disablement came to halt a month later as Pyongyang wrangled with Washington over how to verify its 18,000-page account of past atomic activities. The latest round of talks, in December, failed to push the process forward. On Tuesday, the North said it would restart nuclear facilities, an apparent reference to its plutonium-producing reactor at Yongbyon. North Korea already is believed to have enough plutonium to produce at least about half a dozen atomic bombs. One official at the Vienna-based International Atomic Energy Agency said agency inspectors remained onsite at Yongbyon. He asked for anonymity because he was not authorized to discuss the issue. Asked whether there had been any indication that the North was making good on its threats, he said only that the situation "remained status quo." That suggests IAEA cameras and seals remained in place at the facility and that the inspectors continued their monitoring activities. The Russian foreign minister said all sides must continue denuclearization through the six-party talks. "Any new international forum to discuss the situation on the Korean Peninsula should not be created," Lavrov told a Moscow news conference. "The negotiators of this forum have reached important agreements that impose obligations on all the parties, not only North Korea." Analyst Koh Yu-hwan, a North Korea expert at Seoul's Dongguk University, called Pyongyang's move yet another tactic in the regime's bid to get Washington to the negotiating table outside the six-party framework. "The U.N. statement humiliated North Korea internationally, and that's why North Korea angrily reacted to it," said Atsuhito Isozaki, assistant professor of North Korean politics at Keio University in Japan. "Since China and Russia supported the statement, North Korea feels betrayed." However, Prof. Yoo Ho-yeol of Korea University in Seoul said Pyongyang will find it difficult to boycott the talks entirely, since that would only serve to further isolate the impoverished country, one of the world's poorest. China appealed for calm. "We hope the relevant parties will proceed from the overall interest, exercise calmness and restraint," Foreign Ministry spokeswoman Jiang Yu told a press conference in Beijing on Tuesday. South Korea, expressing "deep regret," also decided Tuesday to fully join the U.S.-led Proliferation Security Initiative, a program launched in 2003 to halt the spread of weapons of mass destruction, the presidential office said. Copyright 2009 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Guidelines: You share in the USA TODAY community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language decent. 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