The New START Treaty limits the number of U.S. and Russian strategic nuclear weapons.

The New START Treaty is a nuclear arms reduction agreement between the United States and the Russian Federation, which was signed on Apr. 10, 2010.

The New START Treaty is a nuclear arms reduction agreement between the United States and the Russian Federation, which was signed on Apr. 10, 2010."Measures for the Further Reduction and Limitation of Strategic Offensive Arms", also called the "New START" (Strategic Arms Reduction), is a treaty signed between the United States and Russia in Prague on April 8, 2010 and came into effect on February 5, 2011. The U.S. Senate approved the treaty on December 22, 2010, by a vote of 71-26. Under the treaty, the parties must meet the treaty’s limits on strategic arms by February 5, 2018. Both countries have the flexibility to determine the structure of their strategic forces within the treaty's aggregate limits.

The treaty restricts the number of deployed strategic nuclear warheads to 1,550. It also limits the number of deployed and non-deployed intercontinental ballistic missile (ICBM) launchers, heavy bombers equipped, and submarine-launched ballistic missile (SLBM) launchers for nuclear armaments to 800. Furthermore, the treaty’s duration is ten years and will expire on February 5, 2021. The involved parties can agree to extend the treaty for no more than five years.

On January 21, 2021, the White House press secretary Jen Psaki said in a briefing said that the Biden administration would seek a five-year extension to the New START arms control treaty with Russia, which expires in February.