THERESA May had a bad day yesterday with the DUP, the EU’s chief Brexit negotiator, and Boris Johnson all rubbishing the government’s Chequers plan.

In a speech in Brussels Barnier said a deal was within reach, it would just involve the Prime Minister giving up on some of her red lines over the Northern Irish backstop.

But the DUP, who prop up the minority Tory government, and Johnson who carries influence with the party’s Brexiteer MPs, made it clear if May conceded on that then she would lose support in Parliament, and could even see her budget defeated when it comes to a vote next month.

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In the past, losing a budget vote generally triggered a general election – though this is no longer the case under the fixed-term parliament act.

But if May and Chancellor Philip Hammond can’t get their budget through the Commons then it’ll become increasingly difficult for them to hold on to their jobs.

The National:

Downing Street were forced to issue a statement saying the Tory leader would be staying in No 10, regardless of what happens at the vote.

The negotiations are reaching a critical stage ahead of next week’s European Council summit.

Barnier said there would have to be customs, VAT and compliance checks on the border.

“Our challenge is to make sure that these procedures are as easy as possible and not burdensome, particularly for small and medium business,” he said in his speech in the European Parliament.

The only way to avoid any border checks on the island of Ireland is to have regulatory alignment between Britain and the EU or have border checks between the UK and Ireland.

DUP leader Arlene Foster made clear that her party would not accept either of those.

Her 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.

Johnson, who resigned as foreign secretary over May’s Brexit plan, warned that May’s agreement of a “backstop” arrangement for Northern Ireland – the clause to make sure that whatever future trade deal is eventually drawn up between the two sides, that there will be no hard border – would leave the UK “a permanent EU colony”.

In a series of tweets, Johnson, said that the deal would keep the UK in the customs union and Northern Ireland in the single market, and would mean increased checks on goods travelling between the province and the British mainland.

The National:

“This is an important moment. Clearly No10 are negotiating a ‘backstop’ that makes the UK a permanent EU colony. We cannot escape EU laws & [European Court of Justice] until they allow us to – which they may never do. That’s not what the biggest majority in our history voted for.

“This backstop keeps the UK in the Customs Union, keeps Northern Ireland in the single market, and almost certainly enhances NI/GB checks. It will apply after 2020 unless the EU agrees it won’t. And they will only agree if we keep our rules in lockstep with theirs.

“This backstop closes off our options. It means we cannot have no deal/WTO or SuperCanada. Under either our rules could differ from the EU’s – so they will keep us in the backstop instead. It means, in fact, that the only possible deal is Chequers.

READ MORE: Applause for Boris Johnson as he rejects Theresa May's Chequers plan at Tory conference

“This is far from #TakeBackControl. In the referendum both sides said Leave meant leaving the customs union & single market. Yet this backstop inevitably means chequers, staying in both, no say in either, and no right to escape. No10 must #ChuckChequers now.

Downing Street insisted that defeat on the budget would not amount to a vote of no confidence in the government because of the Fixed-Term Parliaments Act.

Meanwhile, National Audit Office chief Sir Amyas Morse said it was “not impossible” that flights would be grounded if there was an “unfriendly” break-up with Brussels.