Some MPs said to be prepared to reluctantly back May’s plan as they gather for crunch talks • Brexit deal: latest news and reaction - live updates

Tory remainer rebels were gathering for crunch talks on Wednesday to decide whether to back Theresa May’s Brexit plan, amid suggestions that a number were getting “cold feet” and could reluctantly throw their weight behind the government.

The Guardian understands that at least seven remain-supporting Tory MPs - the former chancellor Ken Clarke and six more who are calling for a second referendum – will vote against a deal, with a further three expected to announce they will join them.

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One remainer rebel, the former attorney general Dominic Grieve, said: “I could not look my constituents in the eye and say this would be a better deal than the one we have as a member of the EU and so I will vote against it.

“Instead I will vote to hand the final decision back to the public. A choice between this miserable Brexit and no deal is no choice at all. The British public deserve a real choice between leaving the EU on these terms or sticking with the deal we’ve got inside the EU.”

However, there were splits emerging among the so-called rebel alliance, with around half a dozen more MPs, who have all voted against the government on Brexit in the past, thought likely to back the prime minister’s plan despite their misgivings.

One MP who is certain to vote against the plan, said: “I have several colleagues who recognise that the proposal has serious flaws but are getting cold feet the closer we get to a vote. They are definitely teetering.”

However, another Tory remainer said: “A lot of us will be looking very carefully at the proposals. It won’t be everything everybody wants but it might allow a number of practical Conservative MPs to back it.”

The broader group of pro-EU rebels, organised by the former minister Stephen Hammond, were gathering at Westminster on Wednesday lunchtime to hammer out their strategy. Invitees included Nicky Morgan, Jonathan Djanogly, Bob Neill, Vicky Ford, Oliver Heald and Jeremy Lefroy.

Insiders said May’s plan looked like it could answer their concerns about economic alignment, especially after suggestions the EU ultimately wanted the UK to stay in a permanent customs union. The group were also “implacably opposed” to the UK crashing out of the EU without a deal, one said.

The second, smaller group of Tory Europhiles, who have called for a second referendum, will hold further talks later in the day. They are all expected to resist the whips’ attempts to win them over and to vote against the deal.

They include former cabinet ministers Justine Greening and Dominic Grieve as well as Sarah Wollaston, Guto Bebb, Phillip Lee Lee and Jo Johnson, who quit his job as transport minister last week describing the choice facing the country as between “vassalage” and “chaos”.

A further three - arch-remainer Anna Soubry and backbenchers Heidi Allen and Antoinette Sandbach – are thought to be considering their options before they make their final decision. One Tory MP said suggestions that the deal could lead to the UK remaining in a customs union permanently might make it more appealing.