Kuznetsov said the incident had not affected plans for their undocking and return to Earth from the station, a $100 billion complex funded by 15 nations that currently hosts a crew of six.

A few hours after the initial reports, RIA cited an official at the private company Akado Telecom as saying the cable break occurred in the Moscow suburb of Mytishchi - near Korolyov, where Russia’s mission control centre is located - but the exact location had not been pinpointed.

Russia’s space program has suffered a series of humiliating setbacks since last year, marring celebrations of the 50th anniversary of the Soviet Union’s triumph in putting the first man in space in 1961. Industry veterans blame the problems on a decade of crimped budgets and a brain drain.