Rebel Tory MPs believe they now have sufficient support to force Theresa May into effectively keeping the UK in the single market.
Conservatives have told The Independent there would be enough of their party’s MPs to lock in full single market access after Brexit, as long as Labour also backs it.
But in a move set to enrage Labour politicians, Jeremy Corbyn’s front bench will on Tuesday refuse support for just such a proposal in the Lords – preventing it from being voted on in the Commons.
Mr Corbyn is now being warned he risks a major internal row and must explain to pro-EU party members why he is “throwing away a clear opportunity” to defeat Ms May’s plans to abandon the single market.
Tory rebels, who joined forces with Labour to shift the government towards closer customs relations with Europe, will now push Ms May towards remaining inside the European Economic Area (EEA) and the European Free Trade Association (EFTA) – which would deliver full single market access.
They say up to 15 Conservative backbenchers are now certain it is the best way to ensure the UK’s economic strength, while also staying true to the 2016 referendum result.
One senior Conservative backbencher told The Independent: “Yes, we have the numbers now, but it will depend on exactly how any particular amendment is phrased.
“It’s more difficult than passing a customs union amendment, because the [Conservative] manifesto was clear about leaving the single market.
“But undoubtedly there are a group of Conservative MPs, now larger than the one who voted for similar amendments in the past, who have concluded maybe it is a way for us to go.”
A vote designed to commit the government to the EEA/EFTA path was lost in December in the Commons, but MPs say things have now changed.
Another Conservative rebel told The Independent: “We have more numbers for this than we had at the defeat in December.
“There are a gang of people who have started saying they are keen on it, a group, up to 15 of us, who think this may well be a good way out.”
Former chancellor Ken Clarke backed the single market in the December vote along with Anna Soubry MP, while other known rebels such as Nicky Morgan, Antoinette Sandbach, Jeremy Lefroy, Paul Masterton and Dominic Grieve have all spoken in debates in favour of the EEA/EFTA route since.
Others who have made supportive comments for the option include Caroline Spelman, Heidi Allen, James Cartlidge, Kevin Hollinrake and John Stevenson. Rebels also say two cabinet members are sympathetic to the idea.
The EEA/EFTA route would also allow the government to escape the European Court’s jurisdiction, but would mean the UK having, to a large extent, to accept the EU’s “four freedoms”.
But Tory rebels argue Britain would have more power than it currently does to impose restrictions on immigration – a driving motivation behind the Leave vote.
Former Conservative minister Stephen Hammond told The Independent: “It allows you to have some conversations over new regulation, in that you are consulted and are part of the process before it comes in, though it’s still not co-determination, of course.
“But the other reason I think it’s a good idea, is that if you look at the EEA terms of reference, it is clear there is more leeway to impose restrictions on freedom of movement.”
The next opportunity to push the government down the EEA/EFTA route comes on Tuesday, when there will be a vote on an amendment to the EU Withdrawal Bill tabled in the Lords by Labour peer Waheed Alli.
Remain-backing Labour MPs want the amendment passed in the Lords, so they can then team up with Tory rebel MPs in the Commons and prevent the government overturning it – in the same way they look set to with other Brexit amendments.
But a Labour front bench source in the Lords confirmed the Alli amendment would not have the party’s official support, saying: “It’s not going to go through. It’s not going to the Commons.”
A Commons frontbench Labour source added: “We don’t believe the EEA/EFTA model is the right one to pursue.
“It was right 25 years ago, it’s right for Norway, but the UK is a different country, a different economy and we’ve never been satisfied that’s the right approach.”
But entrepreneur Lord Alli said that the Labour front bench’s approach “doesn’t make sense”, arguing it is essential for a UK economy heavily reliant on services to be in the EEA, as well as a customs union for goods.
He pointed out that his proposals are backed by founder of Cobra Beer Lord Bilimoria, a crossbench peer, and Tory peers Baroness Verma and Baroness McGregor-Smith, ex-CEO of Mitie Group, adding: “We come from a business background.”
The peer went on: “The front bench of both the Labour and Tory parties are united by the fact that they can’t make clear decisions on the EU, because they don’t want to upset the political balance of their rank and file.
“But Jeremy Corbyn needs to take a decision about our position on Europe. The people that support Labour are pro-European and, make no mistake, when you throw light on his position people are going to see that he still needs to come to the right place.
“They want him to put forward the case for remaining in a strong relationship with Europe. He has got to stand up and represent them.”
One Labour MP who also wants the party’s leadership to back Alli’s proposals, said: “If they don’t there will be a big row. Labour peers will be under heavy pressure to rebel.
“The leadership needs to be honest with members that it is throwing away a clear opportunity to defeat the government’s Brexit plans and ensure full benefits of the single market.”
If Lord Alli’s amendments are defeated on Tuesday and never make it to the Commons, then Tory rebels say they are preparing their own amendments to table to other pieces of legislation at a later stage.
A government spokesperson said: “The referendum was a vote to take control of our borders, laws and money. Ongoing participation in the EEA would mean having to implement new EU legislation automatically and in its entirety without having a say on how it is formulated – and it would also mean continued free movement.
“As the prime minister has repeatedly made clear, we are pursuing a bespoke deal for the UK, which respects the outcome of the referendum. We are negotiating to deliver a bold and comprehensive future economic partnership – with the greatest possible tariff- and barrier-free trade with our European neighbours.”
Join our commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies