The Prime Minister had to break off from lunch with European Commission chief Jean-Claude Juncker yesterday to field an angry call from DUP leader Arlene Foster who had gone public with her concerns.
Before the lunch, EU diplomats and journalists had been told to expect a 15-page document outlining details of a deal that would clear the way for trade talks to begin this month.
But later in the afternoon Mrs May and Mr Juncker faced the Press in Brussels to announce that discussions on a divorce deal had been abandoned for the day.
A senior Tory said the DUP had ‘gone ballistic’ over a proposed compromise which they feared would result in ‘regulatory divergence’ from the rest of the UK and an effective border in the Irish Sea. The party even threatened to pull out of a deal to prop up the Government at Westminster. ‘They are seething,’ the source said.'
DUP MP Sammy Wilson described the proposals as a ‘unionist nightmare’ which could lead to the break-up of the UK.'
Read more: Ten days to save Brexit: Theresa May will spend today desperately trying to persuade DUP and her own Cabinet to resurrect EU deal after Unionists killed plan to sacrifice Northern Ireland with one phone call