Russian officials have postponed the March 30 launch of a rocket carrying a U.S. and Russian crew to the international space station due to a communication problem found during testing.
The Federal Space Agency says the Soyuz TMA-21 mission will go ahead in April, but refused to specify exactly when.
The agency said in a statement Monday that engineers were currently working to repair a part of the rocket's communications system.
U.S. flight engineer Ronald J. Garan Jr. will accompany Russian cosmonauts Andrei Borisenko and Alexander Samokutyayev on the mission. They will join an American, an Italian and a Russian already on the space station. The mission is the first since the retirement of the Discovery Shuttle after 27 years of service.