Theresa May faces a rebellion within her parliamentary party and a vote of no confidence if she abandons her promise of a clean Brexit outside the customs union, Tory MPs have warned.

Over the weekend it was reported that an adviser to the Prime Minister had said her team “will not be crying into our beer” if the UK retain customs ties, which is also likely to mean Britain never regaining control of her national trade policy.

The report follows a group of MPs, including senior Tories, forcing a debate on staying in the customs union, after the House of Lords voted by a strong majority against leaving the union.

The votes are not binding, but give a strong indication as to how parliament will react to a final withdrawal deal taking the UK out the union, which Mrs. May has promised them a “meaningful vote” on.

“She will be crying into her beer,” the MP, a leading member of the Eurosceptic European Research Group headed by Jacob Rees-Mogg, told the IB Times.

UK Will Be ‘Colony’ of EU if It Wants Brexit Trade Deal, Taunts EU Official

https://t.co/6SGG8PLv2y — Breitbart London (@BreitbartLondon) November 9, 2017

“Brexit means leaving the customs union and ultimately if Brexit isn’t delivered there will be a lack of confidence in the government, both in parliament and in the country.

“If that’s the case then we’re heading for a vote of no confidence in the prime minister and a general election. I would support that vote of no confidence.”

“We can’t back down on that. It is so fundamental. I can’t back down on delivering on the will of the people.”

The anonymous MP said that Tory Brexiteers would remain quiet until after the local elections next month, but would then move to defend a clean Brexit.

“There’s an uneasy truce now because of the local elections and we know that voters don’t want divided parties,” they added. “But I can see the bear pit that is being laid for her and I don’t want her to fall into it.”