UNITED NATIONS — The deepest freeze in U.S.-Russia relations since the Cold War has brought diplomatic efforts to halt Iran's nuclear ambitions to a halt just as Western governments and U.N. inspectors are warning that Tehran could be gaining the ability to build a nuclear weapon.
Russia this week pulled out of a six-nation meeting scheduled for Thursday to discuss further sanctions against Iran, freezing for the time being a 3 1/2-year old diplomatic campaign to persuade Tehran to abandon uranium enrichment.
Neither the United States nor Israel has ruled out attacking Iran's nuclear facilities, although there are no overt signs that planning for a military strike has intensified.
The Bush administration's other major effort to curb the spread of nuclear weapons suffered a significant setback Wednesday, when North Korea, which has tested a crude nuclear device, told the International Atomic Energy Agency that it plans to restart a reprocessing plant that produces plutonium for nuclear weapons.
An IAEA spokeswoman North Korea told the IAEA that the U.N. agency's inspectors "will have no further access to the reprocessing plant," IAEA spokeswoman Melissa Fleming said in a statement.
Rice told reporters in New York that if North Korea follows through on the threats, "it would only deepen its isolation." Negotiations with North Korea aren't dead, she said, adding, "We've been through ups and downs in this process before."
The Iran diplomacy, meanwhile, appears to be an early casualty of the growing friction between Washington and Moscow. Secretary of State Condoleezza Rice Wednesday held her first meeting with her Russian counterpart, Sergei Lavrov, since Russia's August invasion of neighboring Georgia.
The meeting had been expected to be testy. Lavrov has privately been contemptuous of Rice, who last week gave a speech critical of Russia, saying the country has taken a "dark turn."
However, after their meeting Lavrov told a New York audience that he and Rice had agreed "to be pragmatic in our relations," despite what he called "emotions and the feelings of being offended" over Russia's actions in Georgia. He also said of the meeting: "I did not feel a rocky style. Certainly a rocky style is not my style."
Lavrov defended Russia's move into Georgia and listed a litany of Russian grievances about U.S. foreign policy. They included the expansion of NATO eastward; U.S. plans to install missile defenses in Poland and the Czech Republic; and President Bush's refusal to negotiate new limits on strategic nuclear warheads.
"The feeling of hostile policies is something that we indeed feel sometimes," he said in an appearance before the Council on Foreign Relations.
Nonetheless, Lavrov said Russia and the United States share the goals of ensuring that Iran's nuclear program is for peaceful purposes and of denuclearizing the Korean Peninsula.
He hinted that Russia backed out of the meeting on Iran in response to the cancellation of other meetings in New York involving the Group of Eight industrialized nations, which includes Russia, saying that Washington cannot chose to cooperate with Russia on some issues and not on others.
While the six-nation talks on Iran — the other participants are Britain, China, France and Germany — had been set for this week, Rice attempted to downplay the Russian move.
"I happen to agree with the Russians that the time is not right. ... We called them. We said ... let's wait and do it when the meeting is prepared," she said in an interview with CNBC.
Iran says it's pursuing uranium enrichment to generate civilian nuclear power, not to build weapons.
Russia has long opposed economic sanctions and, along with China, has delayed and softened past U.N. resolutions on the issue.
But its presence in the talks has given the Bush administration important symbolic cover, allowing it to argue that Iran is defying not just the United States and Europe, but also the U.N. Security Council.
An IAEA report issued 10 days ago said that Iran has blocked the agency's probe into whether it has conducted nuclear weapons research. The report said Iran had made progress installing centrifuges for purifying uranium, significantly boosting the amount of low-enriched uranium it can produce.
Further purification is needed to transform low-enriched uranium into the highly enriched uranium needed for a nuclear weapon. U.S. intelligence agencies estimate that Iran will not be able to build a weapon until after 2010.
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