Jeremy Corbyn will give a major speech on Monday in which he is expected to flesh out his party’s “jobs-first Brexit” policy

Jeremy Corbyn is preparing a major Brexit speech amid mounting pressure for Labour to back Britain remaining in the single market and customs union.

The Times understands that the Labour leader will use the speech on Monday to flesh out the “jobs-first Brexit” policy, which has been criticised for being too vague.

Senior Labour insiders say that they have been sworn to secrecy about the speech, fuelling speculation that Mr Corbyn could announce a new stance on the post-Brexit trading relationship.

Owen Smith, the shadow Northern Ireland secretary, hinted at a change in policy during a TV interview. Asked on ITV’s Good Morning Britain whether he would prefer Labour’s policy to be to remain in the single market and customs union, he replied: “Yes.”

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