Theresa May 'will not quit' if DUP scuppers budget

Theresa May would not be forced to quit if the DUP carried out its threat to vote down the Budget over Brexit, Downing Street has insisted.

Sources within the unionist party rocked Westminster yesterday by threatening to effectively rip up their confidence and supply arrangement propping up May's government if their demands on the Irish border are not met.

Under the terms of the deal struck after last year's election, the DUP received £1bn in funding for Northern Ireland in return for a pledge to support the Government on key Commons votes, such as on a Finance Bill.

But the party is furious at suggestions that extra regulatory checks may be necessary on goods travelling between Great Britain and Northern Ireland as part of the Prime Minister's final Brexit deal.

A DUP source told Sky News: “It is unacceptable that we would be treated differently to the rest of the UK. We will not be bounced into anything.

"If Theresa May doesn't take our concerns on board, she may not be the leader to take us through Brexit."

Asked if the Prime Minister would consider losing a Budget vote a confidence matter - meaning she would almost certainly be forced to resign and the Government would fall - her spokesman insisted she would not.

He said: "I can simply set out the factual position and the answer to that factually is no. The Fixed Term Parliaments Act sets out the circumstances for a confidence vote."

In comments which are likely to further anger the DUP, chief EU negotiator Michel Barnier today said that customs checks on animal products travelling between Britain and Northern Ireland will have to increase tenfold after Brexit.

He said: "Obviously in the future the island of Ireland will remain and must remain a simple epidemiologic area, obviously. 

"Such checks already exist in the port of Larne and Belfast. However they would have to cover 100 per cent rather than 10 per cent of live animals and animals derived products, which would involve a significant change in terms of scale.”

"EU rules are very clear: such checks must happen at the border because of food safety and animal health reasons,”

"There will be administrative procedures for goods travelling from the UK to Northern Ireland which do not exist today. I understand this is politically sensitive, but Brexit is not our [the EU’s] choice."

Meanwhile, Boris Johnson has repeated his claim that Theresa May's Brexit strategy, which was agreed by the Cabinet at Chequers in July and would seek to maintain close economic ties with Brussels, would leave the UK as a "colony" of the EU.

In a series of tweets, he again said the Government should "chuck Chequers" in favour of a Canada-style trade deal - something the Prime Minister has consistently ruled out.