MOSCOW (AP) — An unmanned Russian cargo ship has been launched to take supplies to the six astronauts aboard the International Space Station.

The Saturday launch from Russia's main space facility in Baikonur, Kazakhstan, came after a two-day postponement and docking plan change.

Initially, the Progress cargo ship was to test a new regime for docking with the space station less than four hours after launch. But the Thursday launch was aborted for unspecified reasons, and the ship is now to be in orbit for two days before docking on Monday.

The Russian space agency Roscosmos says the Progress, carrying 2.5 metric tons (2.75 tons) of water, food and scientific equipment, reached orbit about nine minutes after its launch at 0846 GMT (4:46 a.m. EDT).