Collapse of the USSR – in pictures --- The last Soviet president Mikhail Gorbachev initiated reforms that ultimately led to the dissolution of the Soviet Union. Here are some of the key moments: --- Mikhail Gorbachev, head of the Communist party from 1985 to 1991, is a reforming politician who introduces policies of perestroika and glasnost (restructuring and openness) at the 27th party congress in 1986. Photograph: --- US president Ronald Reagan and Gorbachev during a historic fireside chat in a Geneva boat house on 19 November 1985. This is followed by the Reykjavik summit in 1986, culminating in a nuclear non-proliferation treaty in December 1987. Photograph: David Hume Kennerly/Getty Images -- More, Bridget Coaker, Guardian, http://www.theguardian.com/world/gallery/2014/jul/14/soviet-union-collapse-in-pictures