A spokesman for Mikhail Gorbachev says the 85-year-old former Soviet leader is in hospital for a scheduled operation.

Vladimir Polyakov told The Associated Press that Gorbachev was taken to a hospital in Moscow on Wednesday for a "planned, insignificant surgical intervention." He declined to give details, but said Gorbachev was eating normally and was expected to be discharged soon.

Russian media reported that Gorbachev was fitted with a pacemaker in the operation.

Gorbachev has suffered repeated health scares in recent years and in September he canceled a foreign trip on the advice of his doctors.

Since the 1991 collapse of the Soviet Union, the former president has run a foundation for political, social and economic studies.