Civil servants have been told to remove DUP contacts from planning emails which the Northern Irish party would previously have been looped into.
In another sign of deep cracks in Tory relations with the DUP, it emerged on Wednesday that the prime minister had still not spoken to the party’s leader about the draft Brexit deal and it was unclear if she intended to do so before the document was published.
Key figures in the DUP were among the most outspoken critics of the draft agreement reached between British and European Union negotiators, despite details not being available when news of the deal broke.
The instructions to officials suggested Conservative whips have accepted they will not get the support of the DUP for the prime minister’s approach and are beginning to distance themselves from their Northern Irish partners.
According to Whitehall sources, officials were told not to include their usual DUP contacts in any further emails or planning documents.
Correspondence that would typically have been circulated to DUP staff was shut down as of Tuesday evening.
The news comes as the prime minister prepares to announce that the cabinet has agreed to the deal struck in Brussels on Tuesday evening.
Ms May’s spokesman did not comment on the instructions given to civil servants, but at a briefing on Wednesday admitted she was yet to speak to DUP leader Arlene Foster.
Asked when the DUP might see the draft, he said: “Our focus is on the cabinet and as you know cabinet members have been given the opportunity to look at the documentation in advance.”
Asked twice if the confidence and supply arrangement with the DUP is “operational”, the spokesperson said: “It was signed between the two chief whips and the two parties and I’m not aware of any change to it since then.”
Ms May was set to make a statement from Downing Street on the draft deal on Wednesday, while officials in the EU were also preparing a press conference to announce the breakthrough in Brussels.
After the agreement came out, the deputy leader of the DUP, whose MPs prop up Ms May’s minority administration, said the deal as reported would leave Northern Ireland “subject to the rules and laws set in Brussels with no democratic input or any say”.
Nigel Dodds said: “We object to that on constitutional grounds that our laws would be made in Brussels, not in Westminster or Belfast. That is the fundamental red line.”
The critical stumbling block has been over what happens to the border between Northern Ireland and the Republic if no trade deal is secured by the end of the Brexit transition period in December 2020, with Brussels having wanted the north to stay in a customs union with the EU to keep the border open.
Under the “backstop” arrangement said to be in the draft text, the whole UK would remain in a customs arrangement with the EU instead – a condition sought by Ms May – until a future deal is secured, though there would be deeper provisions for Northern Ireland on customs and regulations, something the DUP finds unpalatable.
A review mechanism is also understood to be part of the text, which would determine when the UK would leave the backstop arrangement, but it is unclear whether it meets the demands of Brexiteers – including some in the cabinet – who want Britain to be able to unilaterally walk away.
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