Russia on Tuesday grounded its mainstay Proton-M rocket in the wake of a launch failure that caused the loss of a 242-million-dollar communications satellite, DPA reported.
The government space transport company, Roskosmos, banned further launches of the Proton-M booster pending an investigation into an August 18 launch that left a satellite in an unplanned looping orbit and not responding to commands from ground control.
A communications system problem and an improper firing of the Proton's fifth and final stage have been most often mentioned in Russian media as probable causes for the failure.
Flight controllers on Tuesday declared the satellite lost.
The government had wanted to place the satellite, which was built by a subsidiary of the European Aeronautic Defence and Space Company (EADS), into a geosynchronous orbit to improve communications across the former Soviet Union.
The space vehicle at 5.7 tonnes is the largest satellite ever built by a European company. It had been insured, according to news reports.
The Proton-M has been one of Russia's most reliable launch vehicles, with a success rate of roughly 90 per cent over an estimated 10 years of launches.
The rocket in recent months has performed worse, with failures in December and August out of its last six missions.