LEWES MP Maria Caulfield was one of two vice-chairs of the Conservative Party who quit their posts in protest over Brexit last night.

Mrs Caulfield and Ben Bradley warned the PM her plan would not capitalise on the opportunities of Brexit.

“This policy will be bad for our country and bad for the party,” Ms Caulfield said.

Foreign Secretary Boris Johnson and Brexit Secretary David Davis have already quit over the proposals.

In her letter of resignation Mrs Caulfield said she made the decision “following the collective agreement by Cabinet on the Chequers Brexit deal”.

She added: “Having attended the briefings provided for members of Parliament, I cannot support the direction of travel in the Brexit negotiations which, in my view, do not fully embrace the opportunities that Brexit can provide.”

The so-called Chequers Brexit deal was agreed after a 12-hour summit at the Prime Minister’s country retreat.

It includes an agreement committing the UK to “continued harmonisation” with EU rules - avoiding friction at the UK-EU border, including Northern Ireland.

But the Lewes MP, whose constituency includes Seaford and Newhaven, is not happy with that agreement.

She wrote: “”For me the backstop agreement for Northern Ireland was neither necessary or constructive for the future prosperity of the UK. Having strong links to the Republic of Ireland I feel the backstop position is not appropriate and should have been rejected. It has been used by the EU as a way of blocking a mutually beneficial deal.

“The policy may assuage vested interests but the voters will find out and their representatives will be found out.

“This policy will be bad for our country and bad for the Party. The direct consequences of that will be Prime Minister Corbyn.

“Since the announcement on Friday my constituents, whether they voted leave or remain, have contacted me in large numbers to say they do not support the deal and it would therefore be more appropriate to have a vice chairman who can confidently defend the proposal.

“I want to thank you for the opportunity of being the vice chairman for women, especially during the centenary year of suffrage.

“I will continue to work hard to support the Government in delivering for the British people.”