MOSCOW - Presidents Barack Obama and Dmitry Medvedev on Monday agreed to cut up to a third of the nuclear warheads in their strategic arsenals, but acknowledged that disagreements linger about a proposed U.S. missile defense shield.
Obama and Medvedev stressed that the proposal marked a turn away from the post-Cold War lows of the past few years.
In addition to the conversation about nuclear weapons, Russia said that it would begin allowing the U.S. to ship arms for Afghanistan through the country. Russia and the U.S. also are resuming military-to-military cooperation, a process suspended after the Russia - Georgia war last summer.
Speaking to reporters during Obama's first trip here as president, both men said that they were determined to put the tensions of recent years behind them.
"It is not a simple job, because the backlog of problems is quite impressive," Medvedev said.
Obama said relations have "suffered from a sense of drift," but he and Medvedev were "committed to leaving behind the suspicion and the rivalry of the past."
The recent past includes Russia's invasion of one U.S. ally - Georgia - in August and suspension of gas supplies to another - Ukraine - in January.
The two men, dressed in dark suits and red ties, smiled at each other several times during their news conference in an ornate Kremlin hall, and each nodded frequently in agreement as the other spoke.
The presidents said they'll instruct their negotiators to agree on new limits for strategic, or long-range, warheads to between 1,500 and 1,675 by extending the Strategic Arms Reduction Treaty, which is set to expire in December.
Although the numbers were framed as major news, the figures weren't far from those discussed in recent months. When Obama and Medvedev met in London in April, they said they were aiming for levels below those set by a 2002 treaty that called for 1,700 to 2,200 warheads by 2012. The U.S. is now thought to have about 2,200 deployed strategic warheads and Russia more than 2,700.
The announcement was "a modest step" in the right direction, said Morton Halperin , a former adviser on arms control in the Clinton, Nixon and Johnson administrations. It's "the right way to begin" a new relationship, he said.
For one afternoon in Moscow - a capital used to acrimonious exchange with the U.S. - observers on both sides of the political divide were pleased with the news.
"The new deal is not a breakthrough," said Andrei Kortunov, the president of the New Eurasia Foundation , a Western-leaning research organization in Moscow , "but we have to admit that, at the moment, it is very important to create positively developing relations."
Vyacheslov Igrunov, who heads a government-friendly research organization in Moscow , the Institute of Humanitarian and Political Studies , said the treaty "may be insufficient, but the very fact of making a new deal, a step forward, should not be underestimated."
One cloud over arms control is the split between the U.S. and Russia over a missile defense system the Bush administration proposed in Poland and the Czech Republic .
The U.S. maintains that such a system could counter at most a small number of missiles fired from Iran or North Korea , not a Russian onslaught.
"There is no scenario from our perspective in which this missile defense system would provide any protection against a mighty Russian arsenal," Obama said Monday.
The Kremlin maintains that any anti-missile system close to Russian borders might be expanded to the point that it could counter Russia's nuclear force.
Obama, who's been skeptical about missile defense in the past, said he hoped to convince the Russian leadership otherwise, but added that, "It's going to take some hard work because it requires breaking down long-standing suspicions."
In a joint statement issued later, the two leaders agreed to some modest steps to bridge the gap. They said they would take steps to set up a data exchange center leading to a missile-launch notification system.
In addition, the statement said, experts from each country will conduct a joint review of "the entire spectrum of means at our disposal that allow us to cooperate on monitoring the development of missile programs around the world" - raising the question of whether Russia would be willing to integrate into an American missile defense web.
Gleb Pavlovsky , an analyst in Moscow who's close to the Kremlin, said that the progress with START is encouraging, but Russian leadership remains very cautious about American designs, despite Obama administration rhetoric about building stronger ties.
"This is a sphere of testing the intentions of the United States and their ability to make deals," said Pavlovsky, who has a large picture of Prime Minister Vladimir Putin on one wall of his office, and one of Karl Marx on the other. "The question is what is expected of us? Do they want us to adopt the American agenda as our own? Or do they want to reach a mutual agenda?"
For the Americans, there is equal uncertainty, much of it swirling around the question of whether the reformist posture at times taken by Medvedev is authentic. The Russian president has said that he wants to move against corruption in his country, and toward a more open government that cooperates on a wide range of issues with the U.S.
Putin, widely regarded as the most powerful man in Russia , has struck a harder line, lashing out against the West repeatedly during his eight year presidency and in the past year as prime minister.
In an interview with the Russian newspaper Novaya Gazeta published Monday, Obama said that, "I agree with President Medvedev when he said that 'Freedom is better than the absence of freedom.' So, I see no reason why we cannot aspire together to strengthen democracy, human rights, and the rule of law as part of our 'reset.'"
The setting of the interview was symbolic: Novaya Gazeta has carried articles critical of the Russian government and four of its reporters have been murdered.
It remains to be seen, however, whether this will be the start of a new, more stable relationship between Washington and Moscow .
"It's like reading tea leaves or trying to figure out which way the wind is blowing . . . I think the answer is we're not going to know for a long time," said Sarah Mendelson , a senior Russian expert at the Center for Strategic and International Studies . "I think there are people in and around the Kremlin who want to see a new and different relationship with the U.S. And I'm sure there are people who don't."
Mendelson, who helped organize a summit this week for U.S. and Russian civil society leaders in Moscow , said that even the hint of an opening is worth pursuing.
"We have a unique moment and we'd be silly not to try to take advantage of it," she said.
( McClatchy special correspondent Alla Burakovskaya contributed to this article from Moscow . Grace Chung contributed from Washington .)