Visitors and migrants who use NHS accident and emergency services in England are to be charged, ministers have announced.
The move is part of an extension of the NHS charging strategy intended to deter so-called health tourists while trying to recoup up to £500m a year.
Critics have accused the Government of trying to grab headlines rather than helping the NHS.
Ministers say no-one will be turned away in an emergency, but there will be a bill to pay afterwards for those from overseas.
Health Minister Lord Howe said: "Having a universal health service free at the point of use rightly makes us the envy of the world, but we must make sure the system is fair to the hard-working British taxpayers who fund it.
"We know that we need to make changes across the NHS to better identify and charge visitors and migrants. Introducing charging at primary care is the first step to achieving this.
"We are already looking at taking action and next year we will set out our detailed plans to clamp down on the abuse of our NHS."
Doctors' leaders warned the proposed changes could cost more to administer than they would actually raise for the NHS, while deterring some people desperately in need of treatment from seeking care.
Dr Mark Porter, chair of the British Medical Association (BMA) council, said: "This could mean the system of administering the new charging system will end up actually costing more to run than it collects in revenue."
The announcement has been timed less than 48 hours before restrictions on migrants from Bulgaria and Romania end.
A major influx of immigrants could put additional strain on the NHS and other public services.
Labour argues ministers are putting spin before substance.
Lord Hunt said: "Labour is in favour of improving the recovery of costs from people with no entitlement to NHS treatment. Rather than more grand-standing, the Government needs to deliver practical, thought-through changes to make that happen.
"Instead this out-of-touch Government is left asking doctors and nurses to act as surrogate immigration officials."
Also under the proposed changes, migrants and overseas visitors will have to pay for primary care services such as minor surgery carried out by GPs, while prescription charges will be extended.
There will also be higher charges for services which are subsidised for patients entitled to free NHS treatment, such as optical and dental care.
But consultations with GPs and nurses will remain free of charge to ensure initial access remains to prevent public health risks such as TB, HIV and sexually-transmitted infections.
Details of the scheme are still being worked out and ministers won't have a full plan until March.
But the Government will be hoping its crackdown down on health tourism will resonate home and abroad.
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