Cameron said: ‘When you go back and look at who has done comms jobs in Downing Street and how they have been done, I have to say I haven’t received a single complaint about the way my press office and press communications have been done.
‘I think they work in a very proper, transparent and decent way. That hasn’t always been the case in the past.’
Insiders said Cameron’s comments were a clear reference to the activities of McBride, who was forced to resign as Gordon Brown’s top media adviser in April 2009 after he was caught sending e-mails which discussed smearing senior Tories.
One Tory source said: ‘Compared to McBride, Coulson is a saint.’
It was reported this weekend that Coulson offered to resign for the damage to the government caused by his involvement in a newspaper phone-hacking row dating back to his time as editor of News of the World.
Cameron refused to discuss the report, but said: ‘Of course he was embarrassed, but he has had a second chance from me to do this job. I think he has done the job in a very good way.’