THE HEAD of one of Oxfordshire's largest scientific establishments has become the latest to air his fears over Brexit.

Andrew Harrison, CEO of Diamond Light Source at Harwell, said his facility's success relied on recruiting skilled European workers, but after leaving the European Union 'they may or may not remain'.

Since the referendum he said he had effectively taken on a new job trying to work out the best way for his 600 staff – 15 per cent of them EU nationals – to get through Britain's exit from the EU.

That includes petitioning Oxfordshire MPs and ministers to get the best Brexit deal for the UK science industry.

Mr Harrison spoke ahead of a Royal visit to Diamond on Wednesday by Princess Anne to mark the institution's 10th operational anniversary.

The father-of-three, who lives with his wife and daughters in Steventon, said: "In the field we operate in, Europe has the highest density of of talented people and when we recruit we often find it difficult to get enough skills in the UK.

"We operate well because we can recruit incredibly skilled people sometimes with incredibly rare skills.

"The reality is that depending on the outcome of Brexit, whether they still feel welcome and their legal position, they may or may not remain."

Also well as its own 600 staff, Diamond also welcomes some 5,000 visiting scientists each year – about 20 per cent of them from abroad.

Mr Harrison said it was also imperative that UK-born scientists be able to work and train at European facilities to learn new skills.

The Oxford University chemistry graduate himself worked in Grenoble for seven years and lived there with his family.

He said: "I was able to go there because, within the European Community, my wife could get a job there.

"It's much easier if a whole family and integrate in another country.

"It's not just about getting work visas: fewer people will find it attractive to go across national boundaries if we don't make it easy for their partners and spouses."

Mr Harrison said his biggest concern for Diamond was whether it would be able to maintain strong collaborative networks with sister facilities in EU countries.

Diamond, which is the UK's national 'synchrotron', is a huge particle accelerator which produces a light 10 billion times brighter than the sun.

That light is directed into surrounding laboratories where scientists use it to study molecules in incredibly high detail.

The powerful light is used by researchers from all disciplines, from discovering new drugs to designing catalytic converters and studying fragments of ancient paintings.

Although Diamond as a company is not EU funded, many of the organisations which use its facilities are.

Mr Harrison said: "Diamond can only be strong if the many groups who come to use it are strong, and a lot of the university groups are stronger still because they are part of networks that get EU funding."

His comments come just days after the director of Culham Centre For Fusion Energy 10 miles down the road said his facility faced a 'great period of uncertainty' in the run-up to Brexit.