President Dmitry Medvedev of Russia has signed a law ratifying a nuclear arms reduction treaty with the United States.
The treaty was passed by Russia's parliament this week and the US Congress last month.
It will commit the two nations to ceilings of 1,550 deployed strategic warheads in seven years, up to 30% lower than in the previous treaty.
Each side will be limited to 700 deployed strategic missiles and bombers and establish verification rules, enabling them to keep tabs on each other's arsenals.
Mr Medvedev said Foreign Minister Sergei Lavrov and US
Secretary of State Hillary Clinton would likely exchange documents at a forthcoming meeting. The term of the treaty is 10 years.