The agreement limited the United States to 1,054 ICBM silos and 656 SLBM launch tubes. The Soviet Union was limited to 1,607 ICBM silos and 740 SLBM launch tubes. In June 2002, the United States unilaterally withdrew from the ABM Treaty. SALT II On May 24, 2002, Presidents George W. Bush and Vladimir Putin signed the Offensive Strategic Treaty on The Reduction of Discharges (SORT or Moscow Treaty), under which the United States and Russia reduced their strategic arsenals to 1700-2,200 warheads each. The warhead limit came into effect and expired on the same day, December 31, 2012.  After the failure of the first attempts to reach a comprehensive agreement, the Soviets tried to limit negotiations to anti-ball systems, claiming that restrictions on offensive systems should be postponed. The us position was that limiting ABM systems, but allowing the full growth of offensive weapons, would be incompatible with the fundamental objectives of SALT and that it was important to at least start limiting offensive systems. . . .