He told GP that pressure from these organisations could help persuade ministers to review the use of foreign doctors out-of-hours.

'This is something we have been calling for for months,' he said. 'I have had little success so far, but having this support from groups such as the GMC and RCGP will be a real boost.'

This intervention comes just weeks after health minister Mike O'Brien wrote to Dr Gray to say the government had 'no plans for a broader independent review' of out-of-hours care.

The letter added that the current system, whereby PCOs are responsible for checking the suitability of doctors before entering them on a performers list, provides 'a framework to protect patients from unsuitable or inefficient practitioners'.

Dr Gray said: 'Dr Ubani got off the plane, was tired, unfamiliar with the drugs being used and then killed my father. The system is clearly not safe.'

Dr Ubani was prosecuted in Germany but not in the UK, after giving Dr Gray's father a lethal dose of diamorphine in February 2008. He has been struck off by the GMC, but remains on the German medical register.

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