Mr Johnson said he was impressed by Mr Cameron's PR skills, and his ability 'not to sound Tory' when discussing public services.
Writing in The Guardian, he says Mr Cameron seems to understand what the public wants to hear, but would actually dismantle the patient-centred reforms undertaken by Labour in order to placate health professionals.
'So determined is he to woo GPs that he has opposed our decision to link part of a GP's pay to evening and weekend opening', said Mr Johnson.
'He believes in primary care access being for the convenience of the practice, not the patient. Even more incredibly, he has been so keen for the Tories to be the political wing of the BMA that he signed up to its campaign against new GP-led health centres.'
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