Senators in the United States Congress have ratified a treaty to reduce American and Russian nuclear weapons.
The treaty known as START includes cuts in the number of deployed nuclear warheads.
It was passed by a vote of 71 to 26, the BBC reports.
The agreement trims US and Russian nuclear arsenals to 1,550 deployed nuclear warheads - a cut of about 30% from a limit set eight years ago.
It would also allow each side visually to inspect the other's nuclear capability, with the aim of verifying how many warheads each missile carries.
The treaty must still pass Russia's parliament, which is expected to happen next spring.