The Democratic Unionist Party says it is ready to block the budget and potentially topple Theresa May if she compromises further on Brexit.
The Northern Ireland party – which is propping up the Conservatives in power – dramatically threatened to pull its support if its “red lines” over the Irish border are crossed.
The move comes as the UK and the EU edge towards an agreement that would allow regulatory checks between Britain and Northern Ireland, enraging the DUP.
Arlene Foster has described its red lines as “blood red”, prompting suggestions that the party could join with opposition parties to vote down the budget, on 29 October.
A DUP source told The Independent: “The government is very well aware of what our red lines are and it knows the importance we place on them.”
Asked if that extended to defeating the government in the crucial budget vote, the source replied: “I don’t think that’s a misplaced conclusion.”
Budget votes are viewed as an issue of confidence in a government – meaning defeat could fatally undermine the prime minister’s position and would trigger calls for a general election.
But Downing Street later insisted that losing a vote on the budget would not be confidence issue – and therefore a resigning matter – because the fixed-term parliament act had changed the rules.
The DUP had already threatened to vote against any Brexit deal if it created any new regulatory checks on goods crossing the Irish Sea, even if they take place away from ports.
But extending that threat to the budget is even more serious, because it would rip apart the terms of the “confidence and supply” agreement with the Tories – the “supply” part being money, through a budget.
Until now, Conservatives have been confident that the DUP’s distrust of Jeremy Corbyn would prevent it doing anything that brought Labour closer to power. Read more
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