Immigrants are registering with a GP for free healthcare at a rate of more than one every minute, it was revealed last night. Analysis of NHS research shows that 605,000 people who arrived from overseas registered with a doctor in England and Wales last year – up by 50 per cent in only seven years.

Campaigners say this places a significant ‘strain’ on services and could force patients to wait longer for appointments and treatment.

Doctors are under pressure with the amount of immigrants they have registering with their surgeries. While the number of GPs has increased over the past seven years it has not kept pace with the increase in registrations. The Tories said the GP figures were yet another example of why a cap is needed on migrant numbers.

It is the first time statisticians have examined NHS data on the number of registrations made by people previously living overseas. Of the total, 536,000 were migrants who – under Government rules – were entitled to free care. Others are Britons returning from a stint overseas, but there are fears a proportion of the remainder are illegal immigrants taking advantage of free NHS care.

Sir Andrew Green, chairman of MigrationWatch, which compiled the report, said: ‘This amounts to an open door to primary care which can also lead to access to secondary care. ‘The Government has been dithering while the NHS has been struggling to cope with the extra numbers resulting from mass immigration. ‘In present financial circumstances it is surely obvious that we do not have the resources to cope with the extra ten million people now officially projected over the next 25 years – seven million as a result of immigration.’

There are currently no checks on the entitlement of those who seek to register with a GP. Instead, doctors have discretion to register whoever they choose.

Ministers carried out a review of access to healthcare, which could have led to overseas visitors being barred from receiving some treatments. But, five years after the review was commissioned, the Department of Health said it would maintain the status quo.

Many of those registering for treatment are from Eastern Europe. Doctors have reported an increase in women from the former Eastern Bloc seeking maternity services. However, they also stress most incoming Eastern Europeans are young and in good health.

There are 34,101 GPs in England and Wales. Earlier this month, doctors said more GPs were needed to offer patients the 20 minute appointments which many need. Dr Richard Fieldhouse, of The National Association of Sessional GPs, said one issue was that many of the newly registered immigrants spoke little or no English adding to appointment times. He said: ‘We have to draw diagrams. It takes probably 25 to 30 minutes. We want to do everything we can for them.’

A British Medical Association spokesman said: ‘Doctors’ primary concern is for patients’ clinical need. If people are in the UK legitimately then they have a right to healthcare and there should be adequate resources in place to provide this.’

But Matthew Elliott, of the TaxPayers’ Alliance, said: ‘It is clearly unacceptable that someone who has paid for the NHS throughout their working life should face delays or queues as a result of recent immigration.’

The Department of Health said last night: ‘Access to a GP can have both public health and cost benefits. It is better and cheaper for a GP to treat a patient at an early stage rather than risk an emergency hospital admission when a condition becomes acute.’