The NHS could face paying tens of millions a year in extra immigration costs after Brexit, the Royal College of Physicians (RCP) has warned.
Analysis by the RCP suggested that rising costs, coupled with the potential for European Union nationals to face similar charges to non-EU medics for the first time, could increase pressure on NHS finances.
The RCP's president-elect Dr Andrew Goddard warned Brexit "creates a major risk" and the NHS could soon be spending "up to an extra half-a-billion pounds just to maintain current, already inadequate staffing numbers".
The potential new annual bill of £490 million is based on the most recently available figure of 26,335 overseas health workers joining the NHS in the year to September 2017.
Using the same methodology, the current annual cost, from which EU nationals are exempt, is just short of £140 million.
The £490 million estimate takes into account current visa and associated costs and the 2017 Conservative manifesto pledge for further increases.
Some 12,303 EU staff joined the NHS in 2017 and if they were forced to apply for visas in the same way as non-EU workers, that would add £105 million a year, with a further £45 million if 60% renewed visas after three years.
Factoring in the costs of bringing family members to the UK, the bill for EU workers could amount to £225 million a year.
The £490 million total annual estimate after three years includes non-EU workers who are currently subject to charges.
The Government has yet to set out how the immigration system will operate after Brexit and what costs, if any, will apply to EU migrants.
Currently immigration costs are split between the employer and employee, he said, but the staffing crisis could force some NHS trusts to foot the bill or increase their contributions in order to recruit medics.
"Either way it's clear that the NHS could soon be spending millions and millions more and up to an extra half-a-billion pounds just to maintain current, already inadequate staffing numbers," Dr Goddard said.
"That's up to £490 million that could be better spent on developing our current staff, delivering high quality patient care, delivering integration and driving forward vital quality improvement work."
The impact of Brexit on the NHS has been a major political battleground, with the Vote Leave campaign suggesting during the referendum that the cost of EU membership could be better spent on the health service.
Theresa May has promised that a "Brexit dividend" after leaving the EU will help fund a cash boost for the NHS, although critics have warned the economic impact of leaving the EU could wipe out any benefit from no longer paying into Brussels' coffers.
Labour MP and NHS GP Paul Williams, a supporter of the People's Vote campaign for a fresh referendum, said: "Our NHS relies on the contribution of our colleagues from across the EU, and threatening that would be a needlessly reckless mistake, yet that seems just what the Government wants to do."
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