The prime minister has denied reports that he enjoys a leisurely lifestyle at Downing Street, saying he is "completely dedicated" to his job.
A book on David Cameron by journalists Francis Elliott and James Hanning painted an extremely relaxed portrait of the man in charge of Britain, with reports of four glasses of wine on a Sunday, games on the iPad and a tennis machine at Chequers dubbed 'the Clegger'.
"If I find myself with some spare time I will have a look at this fascinating novel someone has written about me," Mr Cameron said from Chicago, where he is attending a Nato summit.
"It is an enormous privilege to do this job and it is rightly extremely demanding. It requires a huge dedication at work and I am completely dedicated to that," he said last night.
"I think this government has been extraordinarily driven and radical. There are many things this government has done that previous reforming governments weren't able to do," he said.
He added: "Obviously there are constraints of a coalition government, but I would argue that this is a radical reforming government.
"My job now, I think, a lot of time I spend is on making sure we are implementing properly the reforms."
The 'chillaxing' accusations seem light-hearted but they are potentially damaging to a prime minister who is already labouring under accusations of incompetence.
The reports also raise an alarm with Tory backbenchers, many of whom are irritated the government is not pursuing a radical enough programme in government.
The talk of tennis machines and the society high life also cement Nadine Dorries' description of a government run by "arrogant posh boys".