The schools minister Nick Gibb has defended his department’s plans to encourage grammar schools to expand, claiming they will result in “significantly more” help for disadvantaged children.

Although plans to open new grammar schools were dropped last year, the government has created a £50 million annual funding pot, which is on offer to grammar schools that want to expand their sites and take more pupils. In exchange, selective institutions have to prove they’re doing more to let poorer pupils in.

Following his speech this morning to the ResearchED national conference, which promotes the use of evidence in education, Gibb was asked by Schools Week about the research that had informed the government’s policy of promoting selective school expansion.

Gibb said there was “all kinds of research” that shows that the attainment gap between disadvantaged and more affluent pupils narrows in grammar schools, but said this “isn’t the issue that is behind the expansion fund”, and did not expand on his claims about evidence.

“We want any good school to be able to expand, whether that’s a comprehensive school or a grammar school, and that policy goes back throughout this government’s period in office, and indeed pre-dates us.”

He explained that the £50 million fund had been separated from the government’s £1 billion annual budget for general school expansion so that conditions could be attached specifically to grammar school expansion.

“These conditions are that we want evidence that a school is doing more to help children from disadvantaged backgrounds to gain access to that grammar school. And if we’d had that £50 million in the £1 billion, we wouldn’t have been able to apply those conditions. That’s why it’s separated out.”

Gibb accepted the government has been criticised for its proposals, but said it was the “right decision to enable us to apply those conditions”.

“I think what we’ll see as a consequence is those grammar schools that are expanding will be doing significantly more to help children from disadvantaged backgrounds gain a place.”