Under pressure from business leaders in Belfast, the prime minister let slip that she will only seek “changes” to the controversial backstop – not its removal – in fresh talks in Brussels on Thursday.
The comment was seen as backtracking on last week’s Commons vote that it should be “replaced with alternative arrangements”, which Ms May had ordered Conservative MPs to support.
The reaction from the hardline European Research Group (ERG) of Tory MPs was swift, with one source saying: “Even if she doesn’t mean what she said, we still do.”
One prominent Brexiteer, John Whittingdale, pointed out the prime minister had set up a “working party” to explore ideas leading to trade deal that “would not need the backstop”.
“It’s very important that we replace that backstop – that we deal with it – because, currently, it creates a hard border between Northern Ireland and the rest of the United Kingdom, and that’s totally unacceptable.”
The ERG will restate its determination to replace the backstop with – unproven – technology at an event on Wednesday, as the prime minister holds talks with the Northern Ireland parties.
On Thursday, Ms May will meet EU leaders in Brussels for the first time since the crushing defeat of her deal in last month’s “meaningful vote”, but with no specific proposal to break the deadlock.
And MPs will vote again on the crisis just one week later, a concession forced by the threat of cabinet resignations over the growing risk of a no-deal Brexit.
Until her visit to Belfast, Ms May had insisted three options were being considered for reworking the backstop – a time limit, an exit mechanism, or ill-defined “alternative arrangements”.
However, she appeared discomforted by questions from local business leaders and journalists, in the part of the UK where the guarantee – to avoid the return of border points and checks – enjoys strong support.
Asked how she could win support for a deal stripped of the backstop, Ms May replied: “I’m not proposing to persuade people to accept a deal that doesn’t contain that insurance policy for the future.
“What parliament has said is that they believe there should changes made to the backstop.”
Told that some in Northern Ireland believed she had “shafted them”, she said again: “There is no suggestion that we are not going to ensure that, in the future, there is provision for this – it’s been called an insurance policy, the backstop.”
However, the Brady amendment – passed by the Commons last week in a rare show of Tory unity – “requires the Northern Ireland backstop to be replaced with alternative arrangements to avoid a hard border”.
Furthermore, the working group of pro- and anti-EU Tories, under the so-called “Malthouse compromise”, is still exploring those alternatives, with civil service support.
Downing Street tried to repair the damage, insisting all options remained open, including full replacement of the backstop.
But Guto Bebb, a Conservative supporter of the People’s Vote campaign, said Ms May’s comments proved “there won’t be any substantial changes to her Brexit deal”.
“Instead, she’s going through the motions with the EU, letting the clock tick down further, and then will try again to force through her deal that doesn’t command the support of parliament, doesn’t command the support of the public, and is a bad deal for the future of our country,” he said.
Earlier at cabinet, former pro-Remain ministers pushing for an extension to the Article 50 process, if necessary to prevent a crash-out, stayed silent as the prime minister insisted Brexit must still happen on 29 March.
Unless ministers resign to vote for parliament to “take control” next week, it is likely the Commons will again fail to vote to draw up legislation to seek to delay Brexit, extending the stalemate.
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