The Strategic Arms Reduction Treaty (START-1) signed between the Soviet Union and the United States in 1991 places a limit of 6,000 strategic or long-range nuclear warheads on each side. The treaty expires in December 2009.
In 2002, an additional agreement on strategic offensive reductions was concluded in Moscow. The agreement, known as the Moscow Treaty, envisioned cuts to 1,700-2,200 warheads by December 2012. However, that treaty is largely thought to be less effective than the START treaty.
Moscow, which proposed a new arms reduction agreement with Washington in 2005, expects the United States to agree on a deal that would restrict not only the numbers of nuclear warheads but also place limits on all existing kinds of delivery vehicles.
Moscow also insists on the effective use of control mechanisms and procedures, "which the previous administration ignored categorically," according to Foreign Minister Sergei Lavrov.
Obama also said that he would seek Senate ratification of the Comprehensive Test Ban Treaty.
