Labour warned that “crunch time is coming” for Theresa May as the party announced it would oppose the UK prime minister’s plans to take Britain out of the customs union with the EU.
Jeremy Corbyn, the Labour leader, will confirm the policy shift in a speech on Monday. He will also call for Britain to have “a strong relationship with the single market”.
Keir Starmer, shadow Brexit secretary, said on Sunday that a customs union with the EU was the “only way realistically for us to get tariff-free access” to the EU after Brexit. He also cited the need to avoid a hard border between Northern Ireland and Ireland.
“Crunch time is now coming for the prime minister because the majority in parliament does not back her approach to a customs union,” he said.
Labour’s shift raises the chances that Mrs May will lose parliamentary votes on the trade and customs bills, due in the coming months, and on any final Brexit deal, due as early as October. The prime minister is set to make her own Brexit speech on Friday.
Sir Keir signalled Labour would back pro-EU Tory amendments to the trade and customs bills, intended to keep Britain in a customs union. Some Conservative MPs argue that were Mrs May to lose one of the votes, her government would fall.
However, Downing Street has not yet designated the amendments as confidence votes. The votes were initially scheduled for March but have been delayed by the government because of the unfavourable arithmetic.
Sir Keir also said Labour would seek to amend the final Brexit deal. “I don’t think we should any longer accept the proposition that it’s a ‘take it or leave it’ vote,” he told the BBC’s Andrew Marr Show. The government has said that, if parliament amended a Brexit agreement, Britain could end up leaving without a deal.
Mr Corbyn is himself a long-time Eurosceptic who was accused of campaigning half-heartedly for Remain. In a speech in Coventry on Monday, he will continue that balancing act by saying that the EU is not “the source of all enlightenment” and Brexit is not “a disaster” and “does not inevitably spell doom for our country”.
Labour will “seek to negotiate protections, clarifications or exemptions, where necessary, in relation to [EU] privatisation and public service competition directives, state aid and procurement rules and the posted workers directive”, Mr Corbyn will add.
Liam Fox, the international trade secretary, questioned Labour’s commitment to the customs union. “What does that mean? Is it like Turkey, which has a customs union but only in goods, but not in agriculture, not in services, not in finance?” he said.
He called on Conservative MPs to listen to Mrs May’s Brexit speech before making up their mind on whether to vote against the government.
The Conservatives argue that a customs union with the EU would prevent the UK from negotiating trade deals with fast-growing economies, and would prevent Labour from implementing its own manifesto commitment to impose remedies in trade disputes.
The government has also sought to head off a potential rebellion in the Lords over the EU withdrawal bill, which sets the legal framework for Brexit. It said it would amend the bill to introduce a presumption that powers repatriated from Brussels will be devolved to Edinburgh, Cardiff and Belfast but defend its stance of reserving powers relating to trade deals.
Sir Keir argued that Britain would still “have a say” in EU trade negotiations if it joined a new customs union and was more likely to reach deals with the clout of a bigger bloc.
Labour’s change of heart comes after months of pressure from the party’s pro-EU MPs, led by Chuka Umunna, the former shadow business secretary. On Sunday Mr Umunna and others called for Mr Corbyn to go further and commit to membership of the single market.
Separately, Mr Corbyn accepted an apology from Ben Bradley, a Conservative MP who had made defamatory statements about his links with a Czech spy in 1986-87.
“I accept that I caused distress and upset to Jeremy Corbyn by my untrue and false allegations, suggesting he had betrayed his country by collaborating with foreign spies,” said Mr Bradley.
He will pay Mr Corbyn’s legal costs and make a “substantial donation” to two charities chosen by the Labour leader.
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