SCIENTISTS searching for undiscovered life forms in an ancient lake beneath the Antarctic have been forced to call off their mission.

The team, which includes engineers from the National Oceanography Centre in Southampton, believed water samples and sediment under the ice would bring new knowledge about the evolution of life on earth - and even give clues about life on other planets.

But the project has been abandoned for this Antarctic season because the team ran out of fuel trying to link two underground boreholes.

Professor Martin Siegert, who is leading the mission, said drilling down towards subglacial Lake Ellsworth had been running smoothly over the weekend after hitting snags.

But the experiment came to a grinding halt on Christmas Eve because scientists could not form a water-filled cavity 300 metres beneath the ice - despite trying for more than 20 hours.

The cavity was to link the main borehole with a secondary borehole used to recirculate drilling water back to the surface.

Professor Siegert said the link failed “for reasons that are yet to be determined” - but remains hopeful the mission can be completed in future seasons.

He added: “Although circumstances have not worked out as we would have wished, I am confident that through the huge efforts of the field team, and our colleagues in the UK, we have done as much as we possibly could have done, and I sincerely thank them all.

“Sixteen years ago, we hypothesised that deep-water subglacial lakes are viable habitats for life, and contain important records of ice and climate history.

“For now, these hypotheses remain untested. Once back in the UK I will gather our consortium to seek ways in which our research efforts may continue.

“I remain confident that we will unlock the secrets of Lake Ellsworth in coming seasons.”

A unique 5m-long water sampling probe was designed and built by engineers at the city's NOC while the 12-strong team included Southampton engineers Robin Brown and Ed Waugh.

During the process to link the two boreholes, hot water seeped into the porous surface layers of ice and was lost.

The team attempted to replenish this water loss by digging and melting more snow, but their efforts were ultimately in vain.

The additional time taken to attempt to establish the cavity link “significantly depleted” the fuel stocks to such a level that it would not have been possible to complete the operation.

Professor Siegert added: “This is of course, hugely frustrating for us, but we have learned a lot this year. By the end the equipment was working well, and much of it has now been fully field tested.

“A full report on the field season will be compiled when the engineers and programme manager return to UK.”

The Lake Ellsworth Consortium is funded by the Natural Environment Research Council (NERC). It features two of NERC's Centres of Excellence - British Antarctic Survey and the National Oceanography Centre - and nine UK universities.