Ireland’s prime minister has told Theresa May in a hastily arranged phone call that he cannot allow the UK to unilaterally decide when to terminate the Irish backstop, creating the possibility that Britain could be in a customs union with the EU for the long term.
Leo Varadkar’s office released a statement after May called him on Monday morning in which he said while Ireland was open to the possibility of “a review mechanism” for the backstop, the UK could not solely determine how to use it.
“The prime minister raised the possibility of a review mechanism for the backstop,” it said. “The taoiseach (prime minister) indicated an openness to consider proposals for a review, provided that it was clear that the outcome of any such review could not involve a unilateral decision to end the backstop. He recalled the prior commitments made that the backstop must apply ‘unless and until’ alternative arrangements are agreed.”
Downing Street confirmed the call had taken place “to take stock of the progress being made in the negotiations”, and the two leaders had discussed the outstanding issues in the Brexit talks.
A No 10 spokesman said the British and Irish leaders had agreed the backstop would be “a temporary arrangement”, but May had emphasised that there would need to be “a mechanism through which the backstop could be brought to an end”.
The UK statement did not refer to the Irish position that the mechanism could not involve a unilateral decision to end the backstop.
May is under intense pressure from several members of her Cabinet to secure a means by which any backstop agreements can be time limited and able to be terminated by the UK.
The subject is at the heart of the Brexit negotiations, but Varadkar’s remarks indicate there are limits to what Ireland, and by implication the EU, will sign up to.
Cabinet members are due to discuss the Brexit talks today morning at their weekly meeting, but No 10 was earlier indicating that any update for senior members of the British government was not likely to be substantive because insufficient progress had been made.
The EU deems a backstop necessary to ensure there is no return to a hard border between Ireland and Northern Ireland, if the UK and the EU are unable to secure a long-term free trade deal after the end of the Brexit transition period in 2020.
The EU had been looking at a Northern Ireland-only backstop, in which the region would remain in the single market and customs union, but May wants Brussels to accept an alternative UK-wide customs backstop, to avoid creating an invisible customs border in the Irish Sea.
EU officials believe there needs to be “decisive progress” by the weekend for Donald Tusk, the European council president, to be able to announce a summit for the end of November. Without such a development, sources suggested the only viable option would be to leave the deal until the leaders’ summit in Brussels on December 13.
UK officials, however, suggested a summit could be called with a week’s notice, and were indicating that they believed one could be held in the week beginning November 26, just before May and other leaders fly out on 29 November for the G20 in Argentina.
There appears to be a softening on the EU side to an all-UK customs union replacing the Northern Ireland-specific text, but that would require an acceptance by Downing Street that it would in effect be a permanent arrangement.
Earlier yesterday, the Irish Deputy Prime Minister, Simon Coveney, tweeted: “The Irish position remains consistent and clear that a ‘time-limited backstop’ or a backstop that could be ended by UK unilaterally would never be agreed to by IRE or EU. These ideas are not backstops at all  and don’t deliver on previous UK commitments.”

No deal likely this week: Sun political editor
No Brexit deal is likely to be agreed this week between Britain and the European Union and the prospective dates for an emergency summit to seal a deal have been pushed back to November 27 or 28, The Sun newspaper’s political editor said yesterday. “Brexit latest: Whitehall sources say no deal is likely at all this week, nor will Cabinet be asked to decide on any fresh offer to the EU tomorrow,” Tom Newton Dunn, The Sun’s political editor wrote on Twitter. “Prospective dates for an emergency EU summit to agree any deal also pushed back to November 27 or 28,” he said.