 By the mid-1980s, the Soviet contingent was increased to 108,800 and fighting increased, but the military and diplomatic cost of the war to the USSR was high.By mid-1987 the Soviet Union, now under reformist leader Mikhail Gorbachev, announced it would start withdrawing its forces after meetings with the Afghan government.The final troop withdrawal started on May 15, 1988, and ended on February 15, 1989, leaving the government forces alone in the battle against the insurgents, which continued until 1992, when the former Soviet-backed government collapsed.