Proposals to charge more foreigners for using NHS services in England and to fix the "flawed" system for recovering costs have been unveiled.
People from outside Europe staying for up to five years would face an annual charge of at least £200.
Residency rules would be tightened on free treatment and more services, such as access to GPs, would be chargeable.
Ministers say the NHS cannot be an international service but doctors say plans could pose a public health risk.
The consultation document, published on Wednesday, outlines proposals aimed at cutting the cost of migrants' NHS healthcare in England.
- Restricting free treatment for people from outside the European Economic Area citizens to those with indefinite leave to remain in the UK
- Allowing anyone living abroad who has paid National Insurance for at least seven years in the past to get free treatment while on UK visits
- A "health levy" on migrants from outside the EEA staying for up to five years of at least £200 a year - unless they have private health cover
- Improving how non-EEA short-term visitors are identified and charged for hospital treatment
- Extending hospital charges to GP practices and other NHS treatment for non-permanent residents
- Treatment for infectious diseases and sexually transmitted infections to remain free for all
- Improving current "flawed" systems for enforcing current charging rules
- Considering sharing personal information relevant to NHS charges between the NHS, government departments and other agencies
The government says the NHS is one of the most generous systems in the world and is also "open to abuse by those intent on cheating the system".
It does not know how much so-called "health tourism" costs the NHS - estimates range from £12m to £200m a year - but is to carry out an "audit" to work out the extent of the problem.
The Department of Health said the cost of treating foreigners is at least £30m a year for the NHS in England alone - although Dr Clare Gerada, chairwoman of the Royal College of GPs, said that was the equivalent of just two hours of the NHS's annual spending.
The health levy would largely affect foreign students and the £200 figure was considered competitive with what other countries charged foreign students, Health Secretary Jeremy Hunt told the BBC. But it could be set higher and might exclude certain treatments like IVF, cosmetic surgery, organ transplants and antenatal care for pre-existing pregnancies.
Under existing rules, visitors from outside the EEA should pay for hospital treatment - but the government says only a fraction of charges are collected.
It says it will work on improving the system, possibly through "improved technology" to track patients, and stop hospitals being discouraged from identifying foreign patients because they are liable for unrecoverable debts.
It also says it will extend charges to GP surgeries and other primary care for those not eligible for free treatment.
Mr Hunt said the government needed to "ensure that those residing or visiting the UK are contributing to the system in the same way as British taxpayers and ensure we do as much as possible to target illegal migration".
"We have been clear that we are a national health service not an international health service and I am determined to wipe out abuse in the system," he added.
Some doctors have warned they fear being turned into "a form of immigration control" over plans to charge visitors for GP access.
Royal College of GPs chairwoman Dr Gerada said: "My first duty is to my patient - I don't ask where they're from or whether they've got a credit card or whether they can pay."
For Labour, shadow health minister Liz Kendall said people who were not entitled to free NHS care should be made to pay for it but added: "We will have many questions to ask about the details when they are published but the key tests for their proposals are: can they be properly enforced and will they save more money than they cost to put in place?"
She also said plans must "protect the public's health as well as taxpayers' money".
On Twitter, shadow public health minister Diane Abbott said: "What price xenophobia? Stigmatising foreigners accessing NHS creates a public health risk."
The National Aids Trust said the policies would "undermine years of work to encourage marginalised at-risk groups to access HIV testing and treatment".
Chief executive Deborah Jack said "limiting access to primary care for some migrants" would cut off "the only place many of them will get an HIV diagnosis - short of presenting at A&E many years after they were infected once they are very seriously ill".
She added: "If they go ahead, they risk putting lives at risk and accelerating the spread of HIV in the general population."
The Department of Health said people with HIV would still receive free healthcare if the scheme was introduced and Mr Hunt told the BBC there would be an "exemption on all public health grounds" and pointed to other countries which charge for healthcare but did not suffer higher rates of, for example TB, as a result.
The government has previously said a government-wide push to cut "benefit tourism" was being considered in response to "widespread public concern".