Brexit will have implications for the regulation of European doctors entering the country to work, a medical watchdog has warned.
Leaving the European Union (EU) could provide the General Medical Council (GMC), which decides which doctors are qualified to work in the UK, with the opportunity to more rigorously check European doctors hoping to practise in the country.
But the watchdog said it was "far too soon" to predict what would happen, adding that everything would hinge on "whether the principle of free movement is maintained within the treaty of withdrawal".
GMC chief executive Niall Dickson said: "There is no doubt that withdrawing from Europe will have implications for the way that we regulate doctors. However it is far too soon to tell what those implications will be.
"Whatever happens, we want to protect the position of European Economic Area (EEA) doctors who play such a vital role in the UK's healthcare system."
European law currently stops the GMC from testing the competence of European doctors, as it currently does for international medics, which Mr Dickson called "a weakness in the system".
Instead, the independent regulator must rely on "the robustness of the medical education and regulation system in the doctor's home country" when doctors from the EEA exercise their freedom of movement to come and work in the UK.
But the prospect of Brexit means it may become possible to introduce assessments of knowledge and skill for EEA doctors, the GMC said.
Mr Dickson told the Daily Mail: "'I'm not happy with the European doctor situation, and haven't been for many years.
"Some European doctors - because we haven't checked their competency - may struggle when they practise here and that could put patients at risk."
In 2014, the European Commission enabled regulators in Europe, including the GMC, to introduce language tests for prospective health professionals - which Mr Dickson called a "great step forward for patient safety".
Since then, more than 1,100 doctors from Europe have not meet the GMC's English language requirements and so are unable to practise in the UK until they do.
And a week ago the watchdog made the tests for international doctors hoping to work in Britain more stringent, adding new questions on professionalism and ethics.
From September 2017, candidates must pass the written and practical parts of the test within four attempts at each, and will have to apply for a licence within two years of passing,
There are currently just over 21,000 EEA doctors on the GMC's register who are licensed to work in Britain.