A Brexit deal is "within reach" next week, European Union negotiator Michel Barnier said on Wednesday (Oct 10), even as he rammed home his insistence that Britain must accept possible checks on trade between its mainland and Northern Ireland.
Newsnight's Nick Watt said the Northern Ireland party would end its Parliamentary support for the prime minister if she agrees to anything that leads to additional checks between Northern Ireland and the rest of the UK.
Barnier said Brexit would trigger the need for customs, Value-Added Tax and compliance checks with EU standards between Ireland and Northern Ireland in the event that a planned "backstop" were triggered because a future EU-UK trade deal was not sufficient in itself to ensure the land frontier was not a "hard border".
The EU's chief Brexit negotiator has described how a Brexit backstop would affect movement of goods between Great Britain and Northern Ireland.
Yesterday, in what appeared to be an authorised briefing operation, senior DUP sources nearly simultaneously told the BBC and Sky News that it was prepared to vote down the budget.
The European Union has demanded such division if the border with the Republic of Ireland can not be kept open or the entire United Kingdom does not remain inside the bloc's Customs Union - as Mrs May is now reportedly considering after Brexit.
Mrs May told her Cabinet that Britain will not accept an European Union withdrawal deal without a "precise" political declaration setting out how its requirements on trade and security will be delivered.
Mrs May is relying on the support of Arlene Foster's DUP to prop up her unstable Government in what is known as a "confidence and supply" deal.
Steve Baker, Conservative MP for Wycombe, said he believed "at least 40" of his colleagues would vote against a deal along the lines the prime minister has proposed which would include this "backstop" for Northern Ireland.
One complicating factor is that keeping Northern Ireland in the single market would have to be agreed by the Stormont Assembly, which has not met since collapsing in January 2017.
He instead encouraged Britain to make a final push in the talks, offering to launch "around 10 negotiations running in parallel" from April 2019 on an EU-UK trade deal, if agreement can be found now on the Irish border issue and the principles of a Canada-style free trade deal.
"There is progress", Merkel said during a press conference with Dutch Prime Minister Mark Rutte in The Hague, but "everything is solved only when everything is solved".
Commenting on the Irish backstop, Barnier said the EU's plan to keep Northern Ireland in the Single Market and customs union would help keep the border invisible - a goal of both sets of negotiators.
At Westminster, Mrs May told MPs that it was "in the national interest" for MPs from all parties to back the deal she brought back from Brussels.