The letter was signed by 43 NHS consultants

In a letter in the Daily Telegraph, they said proper checks are not being carried out on some foreign doctors.

They said surgeons were being allowed to operate on patients without having to prove they can actually do the job.

The letter was signed by 43 NHS consultants working in hospitals in Cornwall and Devon.

The government has set up new independent sector treatment centres (ISTCs) to try to reduce the length of time people wait for operations on the NHS.

We don't know anything about these doctors Clare Marx, British Orthopaedic Association

The centres specialise in carrying out certain types of surgery, such as hip replacements.

Many are run by private firms and are staffed by doctors brought in from overseas on temporary contracts.

Strict rules

Doctors working in the NHS have to be on a specialist register before they can work as consultants.

In order to get on that register, they need to demonstrate that they have the skills to do the job.

In their letter, the doctors said they were concerned that some of the doctors being brought in from overseas are not having to do the same.

"British consultants have to meet exacting standards by providing evidence of continuing professional education and good clinical governance but the Department of Health appears not to enforce these standards on imported surgeons," they said.

"It is unclear how many unregistered surgeons are operating in ISTCs, but this has occurred."

They said this meant that patients run the risk of being operated on by inexperienced surgeons.

"Of course, there are excellent overseas surgeons, but it is unlikely that the best will want to work here on temporary contracts."

The doctors attacked the government's policy of bringing in foreign surgeons to help it cut waiting lists.

"The whole ISTC initiative appears to be driven by political expediency to reduce the waiting lists, without regard to the quality of surgery and the cost to patients," they said.

"There is no place for foreign surgeons to visit Britain to carry out procedures they may be untrained to perform."

NHS investigation

The letter follows the launch of an investigation into the work carried out by a surgeon at the Royal Hospital Haslar in Gosport.

The doctor, who was brought in from South Africa, has been carrying out orthopaedic surgery. However, two of his patients have had to have corrective surgery after their operation.

Portsmouth Hospitals NHS Trust is now investigating operations carried out on five patients.

The Department of Health insisted surgeons brought in from overseas have to meet the same rules as those already working in the NHS.

A spokesman also defended the policy of using private firms to help cut waiting lsits.

"The government is committed to reducing waiting times now, which is why we are using the independent sector to help provide additional capacity that is simply not available in the NHS."

But Clare Marx of the British Orthopaedic Association said many people were concerned.