If he loses the battle it is quite possible the Trust could end up moving to France with a loss of both jobs and prestige to Britain. The charity, established in 1936 on the death of Sir Henry Wellcome, and with assets worth a staggering pounds 12bn, has become a pivotal player in funding science projects the state sector can no longer afford.
The problem is that while the Government wishes to build the lab in Daresbury, Cheshire, on the site of an existing but now out-dated facility, the Wellcome Trust, which is putting up pounds 110m, is determined the synchrotron, a giant X-ray machine that reveals the structure of molecules, should be sited at the Rutherford Appleton Laboratory (RAL) just outside Oxford.
If the Trust gets its way, the closure of the Daresbury lab would threaten 550 jobs and wreck plans to create a high-technology driven economy in the north of England. As one local Labour MP puts it: "If the synchrotron goes from the North-west, we are stuffed."
The furore could not come at a worse time for Tony Blair, who is desperately trying to persuade the country the North-South divide does not exist.
After several months of behind-the-scenes wrangling, the debate has now been hurled into the public domain. Stephen Byers, the Secretary of State for Trade and Industry, despite being "minded" to build the synchrotron at Daresbury, has postponed a final decision on its location until mid- January, pending further consultation.
The Wellcome Trust accuses Mr Byers of over-ruling his own scientific advisers by plumping for Daresbury on grounds that are not science-based but influenced by social and political issues. The pro-Daresbury camp, however, says the scientific arguments are equivalent and accuses the Trust's board of governors of a South-east bias, based around the so-called "golden technology triangle" of London, Oxford and Cambridge.
All 10 trustees are based in the South-east, although a Wellcome Trust spokeswoman denies any bias, pointing out one of the governors worked in Scotland until 1995.
On Wednesday, Dr Dexter appeared before MPs on the Science and Technology Committee to accuse Mr Byers of making "a unilateral decision [that] had been taken against his own scientific advisers".
Dr Dexter said: "Clearly under these circumstances we cannot support the Secretary of State." He said the trust "would be unlikely to commit our funds if the Secretary of State chooses Daresbury," unless it is shown to be the better site on scientific grounds only.
Dr Michael Clark, a Conservative MP and chairman of the Science and Technology Committee, said: "The Wellcome Trust is putting considerable pressure on the Government. They are saying, `if you want our money, take our terms'. If they withdraw their money, it would lead to the project collapsing."
Scientists at Daresbury are fearful of a last-minute switch to RAL. Dr Graham Bushnell-Wye, a project leader at Daresbury, said: "It seems to me the Wellcome Trust are playing a game that doesn't have any of the normal rules. They can do this because they are a very rich charity. It's put the Government in a very difficult position."
Dr Bushnell-Wye, who moved from the South to take up his post, says a base in the North-west, close to traditional industrial centres, is a bonus. "If you look at the distribution of users," he says, "we are actually pretty central, with leading technology universities at Manchester and Liverpool on the doorstep."
Dr Dexter, however, says moving to RAL is a "once-in-a-lifetime opportunity". He has a vision of creating a super campus for the world's leading bio- technology researchers. RAL is also geographically closer to the Wellcome Trust genome campus at Hinxton, near Cambridge, where scientists, backed by pounds 205m funding from the charity, are attempting to decipher the human genetic code. The synchrotron will exploit data thrown up by the project.
The situation is made more complex because the project has a third backer - the French government, which is pledging pounds 35m. On Wednesday, Dr Dexter claimed private correspondence showed the French clearly in favour of RAL.
All of which has left Labour MP Helen Southworth, whose Warrington South constituency borders the Daresbury site, convinced the Wellcome Trust's preference for Oxford is not based on sound scientific principles. "The main advantage Oxford has over Daresbury is not a better scientific culture," she says, "but better wine at high table."Reuse content