Democratic Unionist MPs who prop-up Theresa May’s Government are preparing to vote against her budget if the Prime Minister breaks their Brexit red lines.
The radical move is one of the options being considered by the DUP if attempts to nail down a deal with Brussels include any proposals that would leave Northern Ireland being treated differently to the rest of the UK, the Press Association understands.
Losing the party’s support in the Commons would mean possible defeat on the budget and a no-confidence vote.
DUP leader Arlene Foster insisted on Tuesday that her party would not accept customs or regulatory checks on goods travelling in either direction between Northern Ireland and Great Britain after meeting EU chief negotiator Michel Barnier in Brussels.
A DUP spokesman said: “The Government is well aware of our position on this issue. Our position hasn’t changed and we don’t expect the Government will change its position.”
The DUP has 10 MPs, although Ian Paisley will not be able to vote in the Commons until November 20 after being suspended for failing to declare two family holidays paid for by the Sri Lankan government.
Mrs May, meanwhile, urged MPs across the Commons to act in the national interest and back a Brexit deal amid warnings that “decisive” progress is needed in the negotiations before a crunch Brussels summit next week.
Mr Barnier briefed top EU officials behind closed doors at a regular meeting of the College of Commissioners on Wednesday, which also heard European Commission secretary-general Martin Selmayr warn of the need to be prepared for “all outcomes” from Brexit.