Former Soviet President Mikhail Gorbachev has reportedly died at the age of 91, according to Russian news agencies.
The Tass, RIA Novosti and Interfax news agencies cited the Central Clinical Hospital. Gorbachev's office said earlier that he was undergoing treatment at the hospital.
Gorbachev was the leader of the Soviet Union from 1985 until its collapse in December 1991.
As general secretary and president, he helped forge weapons reduction deals with the U.S. and other western powers and remove the Iron Curtain.
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