NHS patients are “at risk” because of European laws, the heads of two royal colleges have said.

They claimed “urgent action” was needed on the issue of EU doctors’ language skills, and also criticised the restriction on the number of hours a week trainees can work for.

In a letter to the Daily Telegraph, Prof Norman Williams, the president of the Royal College of Surgeons, and Sir Richard Thompson, the president of the Royal College of Physicians, wrote: “The language competency of doctors from the EU working in Britain, and the stifling effect of the European working time directive on the time that trainee doctors have to learn on the job, need urgent action.

“EU laws that apply to all sectors can have unintended consequences in health care that can put patients at risk, whether in Britain or other member states.”

They added: “The increased mobility of health professionals in the EU has highlighted huge variations both in the practical abilities of professionals of similar grades, and in the systems set up to ensure quality, in different member states.”

The letter also urged the European Commission to introduce an alert system when a doctor is struck off in another country.

Health secretary Andrew Lansley said he had already taken steps to stop doctors with poor English from practising in the UK.

“We agree that for too long patients have been let down by European rules which allowed doctors to operate in the UK without the necessary safeguards,” he said.

“That’s why I announced last year new rules on checking doctors’ language skills and new powers to take action against doctors who can’t speak English properly.”

He added: “We want to revise the EWTD to give the NHS the flexibility it needs on training. Our overriding concern must be to protect patients.”

The EWTD limits the length of a doctor’s working week to 48 hours.