David Cameron looks set to fire a member of his front bench who spoke out in defence of grammar schools in The Times today.

Graham Brady, the Europe spokesman, was “severely reprimanded” by the Tory Party chief whip after he produced data in which suggested grammar schools improve the results of entire neighbourhoods.

Mr Brady suggested that selection at 11 raises GCSE standards for everyone in the area, especially ethnic minority children. This came a day after Mr Cameron called critics of his refusal to bring back grammar schools "inverse class warriors".

A Tory source said that Mr Cameron “hit the roof” over the comments by Mr Brady.

Mr Cameron, along with his chief of staff, Edward Llewellyn, intervened first thing this morning, before the Tory leader flew off on holiday.

A spokeswoman for Mr Cameron said: “Graham has been severely reprimanded by the Chief Whip and told to stick to his brief.”

Mr Brady is now expected to lose his portfolio in next month’s reshuffle.

Mr Brady, a former grammar school pupil, was among the first Tories to challenge the party leadership’s decision to drop a commitment to bring back the system, under which pupils were selected by ability.

He called for an increase in grammar schools in inner city areas in an article on the New Statesman website. This caused his first meeting with the chief whip on the subject. Party sources suggested Mr Cameron was highly unlikely to tolerate a repetition of this transgression.

The Conservative Party is thought not to want a reshuffle at the moment, however. Mr Cameron is believed to be waiting for Gordon Brown to announce his first Cabinet before he reshuffles his own team.

The announcement of the policy by David Willetts, the Shadow Education Secretary, earlier this month led to the sharpest bout of discontent in the Tory ranks since Mr Cameron became leader 18 months ago.

Mr Cameron yesterday declared the row “over”, insisting that he wanted to focus instead on academic setting within non-selective schools in the hope of creating “effectively a ’grammar stream’ in every subject in every school”.

But Mr Brady revived the grammar school debate by releasing data to The Times which indicated that in areas with no selective education 42.6% of pupils get five or more GCSEs at grade A*-C including English and maths, compared to 46 per cent in partially selective areas and 49.8 per cent in areas where all pupils take the 11-plus.

He said: “These facts appear to confirm my own experiences: that selection raises the standards for everyone in both grammar and high schools in selective areas.

“I accept the party’s policy on grammar schools. But it is vitally important that policy should be developed with a full understanding of all of these facts, which might lead to the introduction of selection in other ways, including partial selection in academies and other schools.”

Mr Willetts told The Times today: “Many grammar schools are excellent which is why we are keeping them. But a whole range of serious educational researchers have shown that the chance of an able child from a modest background getting to an academically successful school, whatever their type, is low. That’s the challenge that we have to confront and we are now doing this openly and honestly for a long time with practical ideas on very good schools.”

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