Ireland will not block customs union proposal

As a result, this would see the border effectively running along the Irish Sea. The British government, however, was quick to dismiss Mr Barnier’s offer as “a rerun of old proposals”.

UK Brexit secretary Steve Barclay, on Twitter, rebuffed the Barnier statement.

“With a very real deadline looming, now is not the time to rerun old arguments. The UK has put forward clear new proposals. We now need to agree a balanced solution that can work for both sides,” he said.

With three days to go before a make-or-break House of Commons vote, Mr Barnier warned the UK that time has run out on securing a Brexit deal. He offered a deal that comes with a controversial price-tag. Mr Barnier said if Britain wants to leave the EU on time at the end of this month, the EU will help it by:

Agreeing to legally enforce an “arbitration panel” which will “give the UK the right to a proportionate suspension of its obligations” if the EU “breaches good faith” by not seeking alternatives to the backstop;

This option will come into force at any required point during the two-year with-drawal period which follows the March 29 Brexit divorce date;

It will mean Britain will have the “option” to “exit the single customs territory unilaterally” and help to ensure the “UK will not be forced into [a] customs union against its will”.

However, he said the deal depended entirely on Britain ensuring that “the other elements of the backstop”, those relating specifically to Northern Ireland, “must be maintained to avoid a hard border”.

A Government spokesman said: “These negotiations on the political declaration are taking place between Michel Barnier’s taskforce and the UK. The Government welcomes the fact that Michel Barnier continues to stand up for the interests of the whole of the EU, including Ireland.

“The Taoiseach has repeatedly made clear that he would not oppose a backstop which is specific to Northern Ireland, if that is deemed helpful, but that would have to be a decision for the UK.”

Fianna Fáil Brexit spokesperson Lisa Chambers said “getting a deal over the line would be good for Northern Ireland and I would urge the DUP to think long and hard on this offer”.

Predictably, the DUP rubbished the offer last night, saying the latest deal is “a non-starter” and shows “no respect to the constitutional and economic integrity of the United Kingdom”.

The situation means that unless DUP leader Arlene Foster buckles under growing business and farming pressure to back down, and unless Brexiteers force her hand, the Brexit stand-off has failed to be resolved.

Mr Barnier’s comments came as British prime minister Theresa May gave a keynote speech in Grimsby in which she warned that the UK may “never” leave the EU if MPs vote down her deal on Tuesday.

Describing the coming week as a “moment of crisis” if the EU-UK deal is rejected again, Ms May warned: “Next week, MPs in Westminster face a crucial choice: whether to back the Brexit deal or to reject it.

“Back it and the UK will leave the European Union. Reject it and no-one knows what will happen.

“We may not leave the EU for many months, we may leave without the protections that the deal provides. We may never leave at all.”