Russia on Wednesday lost the ability to send commands to most of its satellites and its segment of the International Space Station following a power cable failure near Moscow.

The Roscosmos space agency attributed the embarrassing malfunction to basic road repair work near the the sprawling Korolyov mission control centre outside Moscow.

Officials said the problem may take 48 hours to fix and could theoretically delay the November 19 return to Earth of three ISS members who are completing their four-month mission on board the floating international space lab.

"We have not had a connection with the ground telemetry stationed in Russia for the past two hours," RIA Novosti quoted an unidentified source in the Russian space industry as saying.

"Our specialists lack the ability to control the civilian satellites or send commands to the Russian segment of the ISS," said the source, while adding the problem could take two days to fix.

"They can see the crew and can talk to them, but they cannot send any commands to the Russian segments."

Russia has suffered a string of failed satellite launches and rocket losses in the past two years that prompted reshuffles at the very top of the country's once-proud space industry.

But the agency has struggled to reform due to chronic underfunding and alleged corruption as well as a long-term inability to replace retiring Soviet-era specialists with fresh talent.

The main subsidiary of Roscosmos is currently the subject of a 6.5 billion ruble ($200 million) embezzlement probe that has fanned speculation over possible new sackings at the very top of Russian space command.

Space officials were quick to put a brave face on the latest public relations disaster by stressing that both the satellites and the space stations remained functional even while being out of control.

"The cable tear occurred during the road repair work... and has not impacted the operation of Russian satellites or the International Space Station," Roscosmos spokesman Alexei Kuznetsov told Interfax.

Another source said that Russia's military satellites were unaffected by the breakdown and continued to function as before.

"What happened is in no way related to the work being done by our specialists with the air and space defence forces," the source told RIA Novosti.

"Communications with the military satellites continue as always," the source said.

The possibility that the cable may take days to fix could delay the return of three astronauts -- including current ISS commander Sunita Williams of NASA and Akihiko Hoshide of Japan -- who had been away from Earth since July.

"This communications cable tear could abort our ability to relay the undocking command to the Soyuz capsule," the unnamed space industry source told RIA Novosti.

Russian officials said they were not currently in control of the space station because it was flying over a segment of Earth within reach of the telemetry stations of NASA.

But Roscosmos will take command of the ISS on Thursday morning Moscow time.

"We hope that the cable will be repaired by then," Gennady Raikunov of the scientific institute in charge of Russia's space communications told Interfax.