An estimated 1,710 of the warheads that can be used by the Russian military are deployed on the likes of intercontinental ballistic missiles or at strategic bomber bases, the organization said. The U.S. has approximately 1,670 deployed strategic warheads, according to the FAS.

Russian President Vladimir Putin lowered the threshold for using nuclear weapons, a move that has sparked global concern, after Ukraine's use of US-supplied missiles to strike targets within Russian territory.

The missiles are significant because they give Ukraine the ability to strike deeper into Russian territory. Russian President Vladimir Putin has threatened to use nuclear weapons if it or neighboring Belarus is attacked by foreign ballistic missile attacks,