Patient records and other NHS data would be shared with private health care companies under plans being unveiled by David Cameron next week.

The Prime Minister is to promise far closer collaboration between the health service and life science companies, including giving them more freedom to run clinical trials inside hospitals.

In a keynote speech on Monday, he is expected to insist that the controversial industry can be a powerhouse of Britain's economy if excessive regulation can be eased.

However, the reforms will encounter strong opposition from privacy campaigners who have consistently opposed wider access to medical records. Labour is also likely to paint the changes as another step towards NHS privatisation by the back door.

With fears mounting that Britain could be on the verge of slipping back into recession, Mr Cameron is due to stress the potential benefits of greater integration between private companies and the NHS. Patients could get faster access to cutting-edge treatments, the Government could save money, and the economy could be boosted.

A Downing Street source told the Sunday Telegraph: "Britain has the potential to become a powerhouse in the world's life sciences industry. We want to see much closer collaboration between the NHS and life science companies - not just greater data-sharing, but more clinical trials in hospitals. These changes will not only boost the industry, but also potentially give the NHS early access to new, innovative drugs treatments."

Ministers believe Britain is uniquely placed to become a world leader in life sciences because of the strength of scientific research at its top universities and the mass of expertise in the NHS. The industry already employs more than 160,000 people in 4,500 companies, and has an annual turnover of £50 billion.

It is not clear whether private firms would be charged for access to NHS records, but data would be expected to be anonymised.

Other government-held data, such as the Met Office's weather records and the most detailed Ordnance Survey mapping is being opened up.

Joyce Robbins, from Patient Concern, said many people would be "deeply disturbed" by the notion that their private medical records could be handed to firms seeking new markets.