The Soyuz TMA-04M capsule with Russians Gennady Padalka and Sergei Revin and American Joseph Acaba on board automatically docked with the ISS at 0436 GMT, Russian mission control said.

The trio blasted off from the Baikonur cosmodrome in Kazakhstan on Tuesday morning in Russia's first manned space launch for almost five months after their start date was put back due to technical problems.

On board the ISS, the three newcomers will join Russian cosmonaut Oleg Kononenko, NASA astronaut Don Pettit and Dutch astronaut Andre Kuipers who have already been on the station almost five months since their December launch.

The hatches are expected to be opened at around 0800 GMT and the three newcomers will then enter the ISS itself and be given the traditional welcome by the incumbent crew.

Their mission has been cut down to an unusually short 126 days due to the launch delay but is expected to be intense, taking in dozens of experiments and the expected arrival of the first private cargo vessel at the ISS.

Private firm SpaceX is seeking to launch its Dragon spacecraft carrying cargo for the ISS on May 19 from Cape Canaveral, Florida in what the company hopes will be the first step towards an eventual private manned mission.