Visiting US President Barack Obama and Kremlin leader Dmitry Medvedev agreed a target for cuts in nuclear arms and a deal to let US troops fly across Russia at the start of a trip intended to mend strained ties.
The United States and Russia agreed today to seek a cut of deployed nuclear warheads to 1,500-1,675 within seven years of a new arms reduction agreement coming into force.
At a cordial, formal news conference in the Kremlin's vast, gilded St Andrew's Hall, the two leaders spoke of their resolve to put differences behind them and focus on cooperating to solve global problems such as the spread of nuclear weapons.
Both mentioned the issues that still divide them - Russia's opposition to Washington's plans for a missile defence shield in central Europe and US insistence on Georgia's territorial integrity - but stressed the positives in public.
Mr Obama praised Mr Medvedev as a "straightforward, professional" leader who understood the interests of the Russian people and wanted to understand those of the United States, adding: "We have resolved to reset U.S.-Russia relations so that we can cooperate more effectively."
At a signing ceremony, the two leaders, wearing identical dark suits, white shirts and red ties, pledged to finalise a treaty by year-end to cut the number of deployed nuclear warheads on each side to 1,500-1,675 from levels above 2,200.
Details of the arms deal were open until the night before Mr Obama's arrival, with negotiators on both sides working through the weekend to secure agreement.
Mr Medvedev described their talks as "very useful and open, businesslike conversations" and said they would aim to build a US-Russia relationship worthy of the 21st century.
Russia will allow 4,500 flights a year carrying US troops and weapons to the war in Afghanistan to cross its vast territory free of charge, a move hailed by the American side as showing Moscow's willingness to help in the war on the Taliban.
Other accords covered the resumption of US-Russia military cooperation, the creation of a new joint government commission, and an exchange of information on prisoners of war, according to texts released by officials.
However, Russian officials repeatedly emphasised in the run-up to the visit that Moscow would not sign an arms treaty later this year unless Obama made concessions on Bush-era plans for an anti-missile system in Europe, a project hated by the Kremlin, which fears it could threaten Russia's security.
Mr Obama has ordered a review of the project, and the leaders played down their differences on it at the Kremlin, saying they had agreed a statement to continue to work together to evaluate global threats from ballistic missiles.
Noting Mr Obama had listened to Russian objections on missile defence, Mr Medvedev used markedly softer language on the issue than Russian officials have done to date.
"No one is saying that missile defence is harmful in itself or that it poses a threat to someone," he told the news conference.
In a slip-up common among visitors confused by Russia's unusual dual power structure, Mr Obama referred at the news conference to a forthcoming meeting with "President" Vladimir Putin before hastily correcting himself.
Mr Putin was out of Moscow on Monday visiting a combine harvester factory in southern Russia.
Earlier Russian Deputy Foreign Minister Sergei Ryabkov greeted the US president, his wife Michelle and their two daughters as they stepped from Air Force One at Moscow's Vnukovo airport.
The arrival was not shown live on Russian television, however, and there was generally little sign in Moscow of the "Obamamania" which has greeted the US leader on some other foreign trips.
The full-scale, two-day US-Russia summit is the first of its kind since the early part of the George W. Bush presidency.
The summit could affect how much co-operation Mr Obama gets in areas in which the US needs help from Russia - chiefly pressuring Iran and North Korea to give up their nuclear weapons ambitions, but also in tackling terrorism, global warming and the economy.
The summit starts a week-long trip for Mr Obama that also features G-8 meetings and a visit with the pope in Italy, and a speech in Ghana.
Reuters