Oxford University and the NHS have stressed the importance of skilled foreign workers to the city as the Government pledged to cap immigration levels.

The pledge comes as new official statistics revealed 23.8 per cent of people working in Oxford are from overseas.

But two of Oxford’s biggest employers said overseas workers played a vital role in the city.

The coalition Government unveiled an interim cap this week, along with a plan to make employers provide non-European Union migrants with private health care to ease pressure on the NHS.

Laura Carpenter, from the Oxford Radcliffe Hospitals NHS Trust, said: “As internationally renowned hospitals, we employ some of the most skilled professionals from the UK and around the world.

“Our overseas staff are an integral and valued part of our workforce, delivering high quality healthcare for the people of Oxfordshire.”

The 50 areas with the highest proportion of foreign workers are dominated by London boroughs. But only seven locations outside the capital have a higher percentage than Oxford, including Reading (29.4 per cent) and Cambridge (28.5 per cent). The statistics do not break down the number of people from the EU, who would not be affected by a cap, and non-EU employees.

Dr Kannaiyan Rabindranath, who lives in Witney and works in the renal unit at the Churchill Hospital, originally comes from Sri Lanka.

The 35-year-old said: “Overseas workers play a vital role at all levels of Oxfordshire’s hospitals, from porters all the way up to consultants. I would estimate about one-third of nursing staff come from overseas.

“There are quite a significant number of junior doctors who come from abroad working as consultants and I think all foreign workers deliver a good level of care.”

Oxford University spokesman Clare Woodcock said 40 per cent of its academic staff and one-third of its students came from overseas.

She said: “Oxford University is a place where the best minds in the world come together to learn from each other and to carry out path-breaking research into a huge range of issues.

“For example, it is because of the pioneering work done in the 1940s by Australian, German and British researchers working together here in Oxford that we have penicillin, the world’s first antibiotic, today.”

She added: “We also believe that it is a vital part of a 21st century education our students encounter people and ideas from cultures and countries different to their own.”

Oxford East MP Andrew Smith said last night: “There is a very real danger by bringing in arbitrary caps, real damage could be inflicted on Oxford’s economy and services.”

The UK population rose to 61.8 million last year. In 2001, it was 59.1 million.

Immigration Minister Damian Green said: “We believe immigration has been far too high, which is why the new Government will reduce net migration back down to the levels of the 1990s – to tens of thousands rather than hundreds of thousands.”