Russia successfully launched cargo ship Progress M-51 early Friday morning from the Baikonur launch pad to deliver food and other cargoes to the International Space Station (ISS).

A Soyuz rocket carrying the craft took off from the Baikonur space center in Kazakhstan at 01:19 a.m. Moscow time (2219 GMT Thursday), and the ship is expected to dock automatically at the ISS on Sunday, said Russian launch officials.

To prepare for the dock, Progress M-50, which had been linked with the ISS for some time, was disengaged late Wednesday night and sank in the Pacific Ocean early Thursday morning.

Progress M-51 carries more than 2.5 tons of cargo, including fuel, oxygen, water, equipment and extra food to supplement stocks that will only last until mid-January.

If it is unable to hook up, the two astronauts, who have been aboard the ISS for two months on a six-month mission, will have to be evacuated from the ISS on Dec. 30 using the Soyuz descent capsule that is permanently moored at the orbiter.

The food shortage came to light during an inventory check conducted on the station earlier this month. ISS Expedition 10 commander Leroy Chiao and flight engineer Salizhan Sharipov have had to cut their calorie intake by 10 percent to make sure that the food onboard would last until the delivery.

Supply problems have persisted at the space station since larger-capacity US space shuttles were grounded in 2003 after the crash of the Columbia shuttle. Russian spacecraft have been carrying out the heavy task of delivering crews and cargoes to the ISS for nearly two years.