FACTBOX: Issues and disputes that define US-Russia ties

(Reuters) - U.S. President Barack Obama will hold a summit with Russian leaders in Moscow next week seeking to "reset" relations that hit a post-Cold War low under his predecessor, George W. Bush.

Following are the main issues and disputes affecting ties between Moscow and Washington:

STRATEGIC ARMS CONTROL

The Obama administration has made reaching a new nuclear arms control pact with Russia the cornerstone of its effort to improve relations between the two largest atomic powers.

Obama and Russian President Dmitry Medvedev agreed in April to move quickly on negotiations to replace the 1991 Strategic Arms Reduction Treaty (START-I), which expires in December.

The leaders are expected during their July 6-8 summit to announce progress and perhaps a framework for a new accord. It is expected to go beyond current arrangements that commit both sides to cutting their arsenals to between 1,700 and 2,200 warheads apiece by 2012. U.S. arms control experts predict the new target could be as low as 1,500 warheads.

A final deal could be hampered by Russia's bid to link the nuclear talks to its demands that Washington drop plans to develop an anti-missile shield in Europe. Russia sees the system as undermining its security. Washington says it aimed at intercepting missiles from hostile states such as Iran.

GEORGIA

Russia's war against Georgia last year caused the worst rift with the West since the fall of the Soviet Union in 1991. Though strains have eased somewhat, Russia remains at odds with the United States and its allies over Moscow's recognition of independence for Georgia's two breakaway regions.

Russia, which has kept troops in the area after crushing Georgia's bid to retake separatist South Ossetia, was angered by recent NATO war games in Georgia proper and has blocked renewal of an OSCE peace monitoring mission.

Washington insists the West will not accept a return to a Soviet-style "sphere of influence" on Russia's borders.

Still, the United States and Russia have an interest in keeping lingering tensions over Georgia from spilling over into other areas of potential cooperation.

NATO EXPANSION

Russia fiercely opposed proposals -- spearheaded by the former Bush administration -- to bring ex-Soviet republics Georgia and Ukraine into the NATO military alliance.

Both states are in a region where the Kremlin says it has "privileged interests" and wants to prevent further encroachment by Western powers.

NATO has said Georgia and Ukraine will join eventually but has declined to put them on an immediate path to membership.