"The confirmation we have is that there has been a failure and that ... the satellite with part of the launcher has fallen into the sea," ESA spokesman Franco Bonacina told Reuters.

The satellite was launched at about 1500 GMT on Saturday on board a Rokot launcher, which is a converted inter-continental ballistic missile.

Equipment on board Cryosat is designed to allow it to take precise measurements of the polar ice caps, which some scientists believe are thinning as a result of global warming and could lead to higher sea levels.

The satellite is reported to have cost $165 million and was to have stayed in orbit gathering data for 3 years.

Russia's Space Troops, a division of the military that runs Plesetsk, confirmed Cryosat had crashed.

"We believe the satellite ... fell where the second rocket stage is supposed to fall, that is in the Lincoln Sea, near the North Pole," Itar-Tass news agency quoted space troops official Oleg Gromov as saying.

POLAR ICE

Existing date suggests that polar ice is melting, but scientists are seeking more definitive information to help them predict changes to the climate and they hoped Cryosat could provide that.

The polar ice caps act as cold stores for massive volumes of water which, if released into the oceans, could leave low-lying cities like New Orleans or London permanently underwater, scientists say.

The crash may deal a blow to Russia's lucrative commercial space launch industry, a spinoff from its nuclear weapons programme which is now responsible for putting a large proportion of the world's satellites in orbit.

Russian space agency Roskosmos ordered a halt into all launches using the Rokot vehicle until an investigation is carried out into what went wrong, Interfax news reported.

That may affect the Dec. 27 launch of the Compsat-2 communications satellite, due to go into orbit on board a Rokot launcher from Plesetsk, reports said.

But Russia's state-owned Khrunichev plant that makes the rockets defended their performance.

"This is the the seventh launch using a converted Rokot and six of them have been successful," said Khrunichev general director Alexander Medvedev, Itar-Tass reported.

Russia's space industry suffered another setback on Saturday when search crews were unable to find an experimental space parachute -- also developed jointly with the ESA -- that floated to earth in the remote Kamchatka region.