British Prime Minister Theresa May sought Thursday to woo MPs with a promise of more power over the next stage of Brexit as she fought to save her EU withdrawal deal ahead of a crucial parliamentary vote next week.
May said lawmakers could have a greater say over an arrangement to avoid border checks with Ireland that could see Britain tied to EU rules for years after it leaves the bloc in March.
The so-called backstop is the key reason many of her own Conservative MPs and her Northern Irish allies opposed the divorce deal, putting her on course for defeat in the December 11 vote.
"People are concerned about the role of the UK in making these decisions. And the obvious, in terms of the UK, is for it to be parliament that makes these decisions," May told BBC radio.
Ministers admit the deal struck with Brussels last month is not perfect but say it is the only option for an orderly Brexit after four decades of membership.
Civil servants on Thursday briefed senior MPs and ministers on plans for a "no deal scenario", which some commentators suggested would focus minds on the implications of rejecting the agreement.
But the scale of the threatened defeat has left some speculating whether May could postpone the vote.
Senior Conservative MP Graham Brady, said he would welcome deferring the vote if it meant clarifying the issue of the backstop.
Former prime minister Tony Blair told reporters at an event in parliament: "Personally I don't see what the point is of going down with a huge defeat."
He said May must work with MPs to establish a way forward that they can all live with, and if not, return the issue to a national vote.
Vote on the future
In Brussels, EU chief negotiator Michel Barnier said the deal was "the only and best agreement possible".
"Now is the moment for everyone to take their responsibilities," he told a committee of regional representatives.
"The British lawmakers will vote on this text and on the future relation in the next few days. It is a vote on which the future of their country depends."
Opening the third of five days of debate on the deal, finance minister Philip Hammond also said it was "a delusion" to believe another deal could be negotiated.
But with more MPs declaring by the day they will oppose the agreement, May faces an uphill task getting it passed - and failure could also spell the end to her own premiership.
She commands only a slim majority in the House of Commons thanks to a deal with Northern Ireland's Democratic Unionist Party (DUP), but the DUP is fiercely opposed to her plan.
The opposition Labour Party has said it could propose a confidence vote if May loses next week.
However, DUP deputy leader Nigel Dodds said that if that happened, he would back her.
"Having achieved our aim trying to get to a better deal, it would be illogical then to turn around the next day and say 'let's vote the government out'," he told ITV.
"I think then we start on a process to try to get a better deal."
May will return to Brussels for an EU summit next Thursday, although the bloc says it considers the divorce deal closed.
'Just not possible'
The backstop is an arrangement intended to avoid border checks between British Northern Ireland and EU member Ireland by keeping both in a customs arrangement after Brexit.
It would only come into effect if London and Brussels fail to agree a new trading relationship by the end of a post-Brexit transition period, in December 2020.
But official government legal advice says the backstop could see Britain left indefinitely in the new customs arrangement, with no power to unilaterally withdraw.
Under May's deal, if the new trade deal is not ready in June 2020, Britain will have an option to extend the transition for up to two years to avoid going into the backstop.
May has suggested parliament make that choice, but former foreign minister and leading Brexit supporter Boris Johnson rejected that idea.
"This is simply not possible," he tweeted.
"Under her deal, the EU has the legal right to stop us extending the transition and make us enter the backstop -- whatever the PM or parliament says."