On 5 December 1994, The START I Treaty went into force, bringing about reductions in nuclear-capable bombers and missiles. The treaty barred its signatories from deploying more than 6,000 nuclear warheads and a total of 1,600 intercontinental ballistic missiles (ICBMs) and bombers. START negotiated the largest and most complex arms control treaty in history, and its final implementation in late 2001 resulted in the removal of about 80% of all strategic nuclear weapons then in existence. Proposed by US President Ronald Reagan, it was renamed START I after negotiations began on START II. The treaty expired on 5 December 2009.