Up to 170 new jobs are to be created at Culham nuclear research centre in Oxfordshire.

Recruitment has already started for 100 jobs with the UK Atomic Energy Authority, which operates the giant Jet European nuclear fusion machine, as well as the UK’s fusion machine Mast.

These staff will all be on permanent contracts, although Jet — the biggest nuclear fusion project in the world — is due to close some time after 2014, when the work will transfer to another international project called Iter in France.

About 30 engineers are needed to work on Jet, Mast and on preparations for Iter. The UKAEA is also recruiting another 70 permanent staff.

In a few months’ time, an extra 70 engineers will be hired by UKAEA on short-term contracts to upgrade Jet, which will be shut for a year to install new equipment which needs to be tested for Iter. Their contracts will end in early 2011.

Iter, now being built in Cadarache in the South of France, is intended to be the final step towards a nuclear fusion power station, producing limitless energy without the need for fossil fuels.

Supporters of fusion say it is clean and cheap, and inherently safer than nuclear fission, which is used in current nuclear power stations.

But it has taken far longer than expected to perfect the techniques needed to release the energy that powers the sun, stars — and the H-bomb — by sticking hydrogen nuclei together.

The Jet machine heats and squeezes a gas so hot that the electrons are stripped away from the atomic nuclei to form a lively and difficult-to-control sub-atomic soup known as a plasma.

Some of Jet’s 400-500 staff will gradually move to Iter from 2010, with others transferring to the UK’s own fusion research programme, which employs 150 people at Culham.

But no-one knows what will happen to the rest of the workforce. When Jet arrived at Culham in 1983, bringing international prestige and hundreds of jobs, the European Commission agreed to restore the site after the project finished.

A public consultation about the future use of the site last summer showed 70 per cent of respondents wanting to see the Jet experimental facilities being retained, with less than ten per cent in favour of removing the buildings and returning the site to farmland.

Spokesman Nick Holloway said: “The feeling is that some kind of scientific research will continue on the site.”