Voters will not forgive Theresa May if she surrenders to Brussels in the Brexit negotiations, Boris Johnson and David Davis have warned.

In an open letter to the Prime Minister, they claim her plans for future relations with the European Union are less popular than the poll tax and call on her to “deliver the Brexit which people voted for”.

It was signed by former Cabinet ministers Mr Davis, Mr Johnson, Iain Duncan Smith, Owen Paterson and Priti Patel, as well as Jacob Rees-Mogg, chairman of the Conservative European Research Group of Brexiteer Tories.

The letter, published by The Telegraph, states: “We urge you to make clear that you will not bind the UK into the purgatory of perpetual membership of the EU’s customs union, whether by a backstop or any other route.”

It adds: “Talk of either a UK or a Northern Irish backstop is inimical to our status as a sovereign nation state. Both are unnecessary: indeed they are a trap being set by the EU which it is vital we do not fall into.”

Jacob Rees-Mogg
Jacob Rees-Mogg is among the Tories to have signed the letter (Aaron Chown/PA)

The group called on Mrs May to “reset” the negotiations and ditch her Chequers Brexit blueprint.

“We urge you not to engage in a show of resistance and a choreographed argument followed by surrender and collapse into some version of the backstop and Chequers,” they wrote.

“Instead we urge you to say to the EU at the summit: ‘Let us agree that we need to reset our negotiations. Our objective is a free trade agreement that benefits the UK and EU and millions of our citizens.’

“This would command a majority in Parliament, unlike the unpopular Chequers plan. Let us seize the opportunity and create a better future for the UK.

“We are close to the moment of truth. Brexit offers the prize of a better future, global free trade deals and political independence.

“But if these potential gains are sacrificed because of EU bullying and the Government’s desperation to secure a deal, the British people will not forgive us.”