THERESA May has managed to secure a draft Brexit agreement with Brussels, but she faces almost certain defeat in the Commons after conceding to European demands for a border in the Irish Sea.

Brexiteer Tory MPs and the DUP were furious last night, and made clear their opposition to the deal.

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There was pressure, too, on Scots Tory leader Ruth Davidson and Scottish Secretary David Mundell.

They recently told May they could not “support any deal that creates a border of any kind in the Irish Sea and undermines the Union or leads to Northern Ireland having a different relationship with the EU than the rest of the UK”.

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Details of what exactly negotiators in Brussels have agreed were not widely known last night, but Tony Connelly, a journalist with Irish broadcaster RTE, reported that it

included a UK-wide backstop arrange-

ment, that would have “deeper provisions for Northern Ireland on the customs and regulatory side” than in Scotland, England or Wales.

SNP MP Stephen Gethins, the party’s foreign affairs and Europe spokesman, said that if a closer relationship between Northern Ireland and the EU can be agreed, “then the same can apply to Scotland”. If the UK Cabinet fails to back the Prime Minister’s backstop plan today, the EU will be unable to sign off on any deal this month and the two sides will have to wait until a further meeting in mid-December.

Key ministers – those thought to be on the verge of resigning – were called into Downing Street last night to be briefed by May.

Mark Francois, deputy chairman of the influential Brexiteer European Research Group, called on his colleagues in government to take a stand.

He told The Telegraph: “What members of the Cabinet do over the next 24 hours is the most important thing that they do in their lives. They have an opportunity to stand up for their country and defend its destiny. We very much hope that they will take it.”

Boris Johnson, the former foreign secretary, was scathing. At an impromptu press briefing in the Commons, he told the BBC: “This has been a ‘Chronicle of a Death Foretold’ for some months.”

He added: “We are going to stay in the customs union, we are going to stay in large parts of the single

market. It’s vassal state stuff as, for the first time in 1000 years, this Parliament will not have a say over the laws that govern this country.”

The DUP’s deputy leader, Nigel Dodds, said his party’s agreement to prop up the Government could be broken.

Nicola Sturgeon said it was clear May’s deal satisfied no-one and “can’t command a majority”. The First Minister added: “We mustn’t fall for her spin that the UK crashing out of EU without a deal is then inevitable – instead we should take the opportunity to get better options back on the table.”

SNP MEP Alyn Smith called on the Scottish Tories to “look to their consciences”.

“David Mundell and Ruth Davidson blustered weeks ago that this would be a resignation matter for them and now they must, in full view of the people of Scotland, justify why we are being sent to the back of the bus and dragged out of the EU against our will and without their efforts,” he said.

Mundell, however, welcomed the news that an agreement had been reached.

On his way into the joint ministerial council at the Cabinet Office last night the Tory minister said: “I think it’s encouraging there’s a potential agreement.”

He added: “That’s what the Government has been working for all this time, to get a deal, and negotiators have worked incredibly hard to get us to this point, but we have to reflect on the detail and consider it at Cabinet”.

The development emerged as the European Commission announced it was stepping up preparations for a no-deal Brexit

A document on travel arrangements published by the Commission said UK nationals would be barred from the fast lane at European airports and ports.

It said Britons “will not be entitled to use the separate lanes” for citizens of the EU, European Economic Area (EEA) and Switzerland “and will be subject to thorough checks of all entry conditions for third country nationals upon entry”. It added that those staying in EU nations for more than 90 days would require a residency permit or a long-stay visa issued by the country they are staying in.

The Commission added that UK citizens travelling to EU nations after Brexit should not have to obtain an entry visa if Britain leaves without a deal – as long as the UK agreed to implement a similar arrangement for EU citizens.

Senior Brussels officials had discussed yesterday whether UK nationals should be treated as “third country” nationals as part of its no-deal planning, which would require travellers to buy a €60 (£52) permit to visit the continent.