Junior doctors who go abroad to work after benefiting from £220,000 worth of world-class training should be forced to pay back some of their costs to the NHS, healthcare leaders say.

Niall Dickson, the head of the NHS Confederation, which represents senior managers, said shortages of staff were now the most pressing concern facing the health service, as he called for major changes to retain more medics.

The former head of the General Medical Council said the NHS should consider forcing doctors to remain loyal to the NHS, by making them commit to at least four years’ service, as happens in the military.

Jeremy Hunt, the health and social care secretary, floated similar ideas at the Conservative Party conference in Autumn 2016, when he set out plans to train an extra 1,500 doctors a year.

However, the idea of penalties for those who leave Britain soon after completing medical school was put on hold, amid increasingly bitter tensions between the Government and medics over a new contract for junior doctors.

Senior managers are concerned that growing pressures on NHS hospitals could entice doctors to seek a new life in countries such as Australia, New Zealand and Canada, which recruit high numbers of medics from the UK.