Labour’s shadow education secretary vowed to “fight with every breath in my body” to defeat Theresa May’s grammar school proposals, which she branded as “toxic”.

Angela Rayner said her party was launching a nationwide campaign on Saturday to attack the prime minister’s plans, as she warned more grammars would “embed inequality”.

The MP for Ashton-under-Lyne accused Ms May of telling “fairytales” about social mobility and opportunity.

In an impassioned speech at the Labour Party’s annual conference in Liverpool, Ms Rayner dismissed Ms May’s claim that more selection in schools would create a “true meritocracy”.  

“Let me tell her that every child has merit,” Ms Rayner said. “That is why I will fight, with every breath in my body, against her new grammar schools.

“She has produced no evidence that grammar schools help social mobility. Selection - or segregation as it should be called - entrenches division and increases inequality.”

The Labour politician, who has been tipped as a future leader of the party, re-iterated her quote that while Tony Blair talked of “education, education, education”, Ms May wants “segregation, segregation, segregation”.

“Theresa May is telling fairy tales about social mobility and opportunity,” she warned. “Selection is toxic. It tells a clever child they are stupid, strips a child of self-esteem and embeds inequality. Every child has potential. Every child can succeed. No child should be left out or left behind.”

Labour is to hold a “national campaign for inclusive education for all” on Saturday against the government’s grammar school plans.

Ms Rayner also called for more effort to be put into improving technical and vocational education, and spoke of her pride that Labour has pledged to bring back the Education Maintenance Allowance.

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