Mikhail Gorbachev, the last leader of the Soviet Union, is suffering from a serious kidney ailment, according to a report on Russia's Mash Telegram channel.
"The former president of the USSR has to travel for dialysis," Mash said on its channel on Monday.
The 91-year-old who presided over the opening up of the Soviet Union in the late 1980s was suffering repeated health problems, it added.
Gorbachev had undergone repeated medical examinations over the past year, Mash said. It added that the former leader now had to undergo dialysis to purify his blood. There has been no official confirmation that he is suffering with his kidneys.
Gorbachev became general secretary of the Soviet Union's Communist Party in 1985, a position that placed him at the head of the country's political hierarchy. In 1990, he became its first and last president.
During his time in office, Gorbachev introduced reform and openness of the communist system under the terms "perestroika" and "glasnost." The Soviet Union dissolved in 1991.
At the start of the year, relatives of Lithuanians killed as the Baltic republic broke away from the Soviet Union more than 30 years ago, lodged a charge against Gorbachev for failing to prevent Soviet troops from suppressing the Lithuanian independence movement.
Fourteen civilians were killed and 700 were injured in clashes with Russian forces in the capital of Vilnius on January 13, 1991.
Australian Associated Press
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