Obama, Medvedev to seek nuclear breakthrough at Moscow summit.
U.S. President Barack Obama and Russian President Dmitry Medvedev are to meet in Moscow on Monday in hopes of pinning down an outline of a new deal that would reduce vast arsenals of Cold War nuclear weapons.
The bilateral summit follows their first encounter in London in April, when they agreed to launch negotiations on a successor to the Strategic Arms Reduction Treaty, or START 1, which runs out Dec. 5.
A breakthrough in the negotiations, several rounds of which have already been held, would mark a thaw in often-rocky relations between the world's two biggest nuclear powers.
Ties between the United States and Russia plunged to their lowest point last summer since the end of the Cold War over a war in the former Soviet republic of Georgia, a U.S. ally.
Obama, who is calling for a nuclear-free world, and Medvedev have said the envisaged nuclear arms control pact should cut arsenals below those in the 2002 Strategic Offensive Reductions Treaty, under which both sides are to pare their stockpiles to between 1,700 to 2,200.
Signed in 1991, START 1 resulted in significant reductions in the two countries' nuclear arsenals. It limits the number of deployed warheads on both sides to 6,000 and the number of delivery systems -- the rockets or other means that deliver weapons -- to 1,600.
Any prospective new nuclear deal could be torpedoed by differences between Washington and Moscow, including the U.S. pursuit of a missile defense system in Europe and its support of North Atlantic Treaty Organization expansion.
The two sides are poles apart on U.S. plans to station an antimissile system in Poland and the Czech Republic, something which Moscow says would threaten its security. Washington insists they are aimed solely at averting a potential attack from Iran.
Russia is also opposed to NATO's expansion eastward and indignant that the United States has left the door open to membership for Georgia and Ukraine, another former Soviet republic.
Nuclear arms control will be the primary objective of Obama's Moscow visit. But the U.S. leader is also eager to drum up Russia's support on a plethora of pressing global issues.
''We want to actually do real business with the Russians on things that matter to our national security and our prosperity,'' said Michael McFaul, senior director for Russia and Eurasian affairs at the National Security Council.
Obama and Medvedev will compare notes on ''Iran, Afghanistan, North Korea, nonproliferation, European security -- all the issues that matter in terms of American security and prosperity and the security of our allies,'' McFaul told reporters.
Washington is hopeful of securing Moscow's consent to ship lethal military supplies to U.S. troops in Afghanistan across Russian territory -- an urgent priority as existing supply lines across Pakistan become less safe.
On Tuesday in Moscow, Obama will meet with Russian Prime Minister Vladimir Putin, who many see as the power behind the throne in Russia, as well as with former Soviet President Mikhail Gorbachev.
Russia will be Obama's first stop in a weeklong trek that will also take him to Italy and Ghana.
In Italy, he will attend the annual Group of Eight summit. The leaders of the G-8 -- Britain, Canada, France, Germany, Italy, Japan, Russia and the United States -- will also hold expanded talks with their counterparts from other major nations to discuss African development and climate change.
Ghana will be the first African country for Obama to travel to since taking office in January. His plans in the West African country include a speech and a visit to a castle that once served as a hub for slave trade.