A Russian cargo ship carrying badly needed food supplies for a U.S.-Russian crew on the international space station (search) blasted off from the Baikonur cosmodrome early Friday.

The Progress M-51 (search) took off from the Russian-leased launch pad in the steppes of Kazakhstan and entered orbit 124 miles above the earth about nine minutes later, Russia's Federal Space Agency said in a statement.

The ship was scheduled to arrive at the station Sunday morning with about 2.5 tons of food, water, fuel and research equipment for Russian cosmonaut Salizhan Sharipov and U.S. astronaut Leroy Chiao, who are in their second month on the station.

Russian and American space officials were alarmed earlier this month to learn that Sharipov and Chiao had gone through much of their food on the station.

NASA (search) officials said there was food to last seven to 14 days beyond Dec. 25 if the supply ship did not arrive. They called the situation "critical."

The crew was 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.

Officials at the Russian Mission Control in Korolyov just outside Moscow sought to downplay concerns, saying the crew has enough food for another month.

"The crew isn't hungry or thirsty," Mission Control chief Vladimir Solovyov said with a grin. "We are running short of food due to the break in shuttle flights, but it would be absolutely wrong to dramatize the situation and say they have nothing to eat."

Russian Soyuz crew capsules and Progress cargo ships have been the only link to the space station since the U.S. shuttle fleet was grounded after the Columbia burned up on re-entry in February 2003, killing all seven astronauts aboard.

The Progress is also carrying Christmas presents for the crew from their families and friends. It is also carrying a German-made robotic device.

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

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.