The government is 'yet to prove the case' for opening new grammar schools, MPs have said.

The Education Committee, a cross-party group of MPs, says ministers are yet to demonstrate how the schools would 'close the attainment gap' between poorer children and their better-off peers.

The government wants to lift the ban on new grammar schools, a drive announced last September, and are offering existing selective schools a share of a £50m annual funding pot for expansion.

MORE: Could Norwich and Fenland get the first of Theresa May's new grammar schools?

In the new 'evidence check' report, published today, the committee says pupils should not be admitted to grammar schools simply by passing a selection test.

There have been calls to create a test which is 'tutor-proof' - and MPs say the government is yet to demonstrate how an admission system would not favour pupils whose parents can afford to pay for a tutor.

They have urged the government to publish a thorough assessment of the impact of introducing new grammar schools, 'given the potential consequences for school funding, the supply of teachers and the overall health of schools in England' from expanding selective education.

MORE: Grammar schools debate - eight key questions and answers

Neil Carmichael, MP and chairman of the committee, said: 'The government has yet to prove the case for opening a new wave of grammar schools. The prime minister rightly talks of making Britain a great meritocracy.

'If the government wants to push ahead with new grammar schools it must demonstrate how this aids social mobility and improves educational outcomes for all, most especially those from disadvantaged backgrounds.'

He said the focus on opening new schools was 'an unnecessary distraction' from ensuring all young people are equipped with the skills to 'compete in the modern workplace'.

'A broadly skilled workforce is crucial to the future success of the UK economy,' he said.

The report follows a hearing in November, when the committee quizzed schools minister Nick Gibb and others on the proposals.

• What do you think of grammar schools? Email lauren.cope@archant.co.uk