BORIS Johnson has refused calls from Labour and the SNP to scrap the "cruel" charge levied on overseas health workers for using the NHS, arguing the UK Government would struggle to find alternative sources of cash to replace the £900 million the fee raised.

During Prime Minister’s Questions, Sir Keir Starmer said many health workers were "risking their lives" during the Covid-19 pandemic but questioned whether it was right that those who had arrived in the UK to work on the front line should pay hundreds of pounds, and sometimes thousands, to use the NHS.

The Labour leader warned a care worker earning the minimum wage would have to work for 70 hours to pay off the fee, which is due to increase from £400 a year to £624 from October.

In response, Mr Johnson admitted he had “thought a great deal about this”.

The PM told MPs: “I do accept and understand the difficulties faced by our amazing NHS staff and, like him, I've been a personal beneficiary of carers who have come from abroad and, frankly, saved my life."

He went on: "On the other hand, we must look at the realities; this is a great national service, it's a national institution, it needs funding and those contributions help us to raise about £900m and it's very difficult in the current circumstances to find alternative sources.

"So, with great respect to the point he makes, I do think that is the right way forward," insisted Mr Johnson.

Sir Keir said he was "disappointed" at the response and said the PM knew "how raw" the issue was.

He confirmed Labour would table an amendment to the Immigration Bill to exempt NHS and care workers from the charge now that Mr Johnson had dismissed the call to reconsider his view.

Later, Ian Blackford for the SNP kept up the pressure on the Government, echoing the call for the immigration health surcharge to be removed immediately, branding it "cruel".

The party leader said: "The Home Secretary[Priti Patel] and the Prime Minister seem hell-bent on implementing a purely ideological immigration policy with no basis in fairness or economics.

“This Government has talked about giving back to our NHS and care staff, well it's time for the Prime Minister to deliver,” declared Mr Blackford.

"People migrating to these nations and choosing to work in our NHS and our care sector must have this Government's cruel NHS surcharge removed and removed immediately.

"Will the Prime Minister make that pledge today or will he clap on Thursday hoping that no-one really notices that he's giving with one hand and raking it in with the other?" asked the Highland MP.

Mr Johnson replied by insisting: "This is the party that is putting more into the NHS - £34 billion - the biggest investment in modern times and believe me we will continue with that investment."

The Commons clash followed the Royal College of Nursing expressing “alarm” that the Government had no plans to exempt foreign health workers from the NHS surcharge.

The nursing union has written to Ms Patel urging her to reconsider the decision and waive the charge "as a matter of urgency" as it ramped up calls it has been making on the subject for two years.

Under immigration rules, workers coming to the UK from outside the European Economic Area are required to pay the fee in order to be able to use the NHS.

Dame Donna Kinnair, the RCN Chief Executive and General Secretary of the union, which represents 450,000 health and care workers across the UK, said: "We are urging the Home Secretary to reconsider and waive this charge for healthcare staff from overseas as a matter of urgency.

"We have already received devastating accounts from members who are struggling to pay the charge and the impact that it is having on their families' lives. The current pandemic has served to reaffirm the importance of our internationally educated staff.

"Without them here, patient care would be at risk. This charge undermines the dedicated care overseas health and care staff provide to us all," she added.