Separately, senior Tory MPs insisted that any deal struck with Labour that involved anything close to a customs union – Corbyn’s central demand in the talks – would be rejected by more than 100 of the party’s MPs, who would see it as a betrayal of May’s promises on Brexit.

Nigel Evans, executive secretary of the 1922 Committee of Tory backbenchers, said: “If there is a compromise that turns out to be a kind of ‘Brexit in name only’ involving anything close to a customs union there would be more than 100 Tory MPs who would never support it, particularly following the local elections.”
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Alanna Vine, chair of Cheadle Conservative Association, said: “Our party’s failure to deliver Brexit has been toxic. If we don’t change course – immediately cease discussions with Corbyn about us remaining in the EU customs union and stop endlessly extending our leaving date – our party will be wiped out for a generation.”

Alexander Curtis, chair of Hertford and Stortford Conservative Association, said: “Colleagues have paid dearly for our prime minister’s failure to believe in and back the decision of 17.4 million voters to leave the EU. People are sick of our incompetence and inability to deliver and to honour our promises. We will be annihilated in the Euro elections if we break another promise and adopt Corbyn’s customs union plan.”

https://www.theguardian.com/politics/2019/may/04/anger-grows-may-corbyn-bid-stitch-up-brexit-deal