A Russian cargo ship blasted off early Thursday carrying badly needed food and equipment for the international space station, where supplies for the American and Russian crew have dwindled to critical levels.

The Progress M-51 took off from the remote Baikonur cosmodrome in Kazakhstan at 1:19 a.m. (Moscow time) with about 2.5 tons of food, fuel and research equipment for Russian cosmonaut Salizhan Sharipov and U.S. astronaut Leroy Chiao, ITAR-Tass and Interfax news agencies said. It was scheduled to arrive Sunday morning.

Russian and American space officials were alarmed earlier this month to learn that Sharipov and Chiao, in their second month at the station, had gone through much of their food. There was food to last seven to 14 days beyond December 25 if the supply ship did not arrive.

The crew has been ordered to cut back on meals. A Russian Space Agency spokesman has said the two could be forced to return to Earth if the Progress does not reach the station.

An independent team was looking into how the orbiting station's food inventory ended up being tracked so poorly and how it can be improved in the future.

Sharipov and Chiao's launch to the station in October was delayed twice -- once after the accidental detonation of an explosive bolt used to separate the ship's various components, and then when a tank with hydrogen peroxide burst due to a sudden change in pressure.

Russian rockets and the non-reusable Soyuz space craft have been the only way Russia and the United States can get to the space station and back since the U.S. shuttle fleet was grounded after the Columbia burned up on re-entry in February 2003, killing all seven astronauts aboard.

NASA has said it plans to resume its shuttle program in May.

Source: Agencies