A Russian Proton-M rocket and a Breeze-M upper stage have successfully guided a fresh telecoms satellite into sub-orbit on Sunday. "The spacecraft and the upper-stage rocket have detached from the third stage of the rocket carrier," Russia's space agency has reported.

After being launched from Baikonur in Kazakhstan at 12:12 GMT by a Russian Proton-M main booster, the Inmarsat-5F1 telecommunications satellite of the British Inmarsat global mobile operator is on its way to a geostationary transfer orbit up to 65,000 km above the earth.

It is expected to settle into this orbit on Monday morning after detaching from the Briz-M upper booster at 3:43 UTC. The Briz booster is yet to be fired five times to psoition the satellite.

The Khrunichev company that developed the Proton and Briz systems says the detached booster will immediately be deactivated to prepare it for safe dead orbiting.

From its transfer orbit, the Inmarsat-5F1 satellite is to proceed to a geostationary position

Proton to launch UK telecom satellite from Baikonur

A rocket Proton-M with the British telecommunications satellite Inmarsat-5F1 will be launched from the Russian spaceport Baikonur on Sunday, the press service of the Khrunichev State Space Research-and-Production Centre said.

"The launch of the telecommunications satellite Inmarsat-5F1 is scheduled at 16:12 Moscow time on Sunday, December 8, from the Baikonur spaceport," the press service reported.

The telecommunications satellite Inmarsat-5F1 will be launched according to the already tested method of orbiting the satellite.

The first three stages of the rocket Proton-M will put the upper stage rocket Briz-M onto a suborbital trajectory carrying the telecommunications satellite Inmarsat-5F1. The upper stage will then bring the satellite to the designated orbit. After that the telecommunications satellite Inmarsat-5F1 will shift to its geostationary orbit by means of its engine and will assume it's position at 63 degrees east longitude.

The British telecommunications satellite will separate from the upper stage rocket 15.5 hours after the launch.

The Inmarsat-5F1 satellite was produced by the U.S. company Boeing Satellite Systems based on the BSS-702HP platform for the British satellite communications operator Inmarsat Plc. The launch weight of the satellite will be more than six tonnes.

The Proton-M launch vehicle is an upgraded modification of the rocket Proton-K with improved energy-mass, operational and ecological features. The first launch of the rocket Proton-M with the upper stage rocket was on April 7, 2001.

The Russian-U.S. joint venture International Launch Services Inc. (ILS) was contracted to launch the Proton rocket.

Voice of Russia