U.S. and Soviet/Russian Strategic Nuclear Forces

START I was signed July 31, 1991, and entered into force on December 5, 1994. Under the treaty, the five parties—the United States, Russia, Belarus, Kazakhstan and Ukraine—semi-annually exchange memorandum of understanding (MOU) data providing numbers, types and locations of accountable strategic nuclear weapons. The tables below compare the number of START-accountable deployed warheads declared in the initial September 1990 MOU with data from the July 1998 MOU, demonstrating the progress the parties have made in nuclear force reduction thus far.

Warheads by Delivery System¹

Warheads by Delivery System¹

1. Warhead attributions are based on START I counting rules. This results in bombers having fewer warheads attributed to them than they actually carry. On the other hand, even though all nuclear warheads from Ukraine have been removed to Russia, they remain START-accountable until the delivery systems have been destroyed. [Back to Table 1 , 2 or 3]

2. Includes weapons in Belarus, Kazakhstan, Russia and Ukraine. [Back to Table]

3. Weapons in Russia only. [Back to Table]

4. Also known as the TOPOL-M or RS-12M Variant 2 ICBM. [Back to Table]

Sources: START I Memorandum of Understanding, July 1, 1998; ACA.