Jean-Claude Juncker piled the pressure on MPs to back Boris Johnson’s last-minute Brexit deal by raising doubts over any further delay to the UK’s departure from the European Union.

The European Commission president said there would be no further extension to Article 50, after the Prime Minister called on Parliament to “come together and get Brexit done”.

EU leaders approved the new Brexit deal at the key summit on Thursday, paving the way for a parliamentary showdown after the Democratic Unionist Party ruled out backing the agreement.

Following days of intense negotiations, the PM announced that he had struck a “great new deal” shortly before heading to the Brussels meeting.

But it must still be passed by a Parliament which has so far proved hostile to both Brexit and Mr Johnson.

His key ally, the DUP, emphatically ruled out voting for the new deal, citing a series of objections over the integrity of the Union, the Good Friday Agreement and Northern Ireland’s economy.

Mr Juncker, after holding a face-to-face discussion with the PM, told reporters the deal “has to” be approved by Parliament.

“Anyway there will be no prolongation,” he added, on the October 31 deadline.

“We have concluded a deal and so there is not an argument for further delay – it has to be done now.”

Tory leadership race
Boris Johnson with Arlene Foster (Niall Carson/PA)

However, whether any requested extension is granted is not down to Mr Juncker – it requires the consent of the 27 remaining members of the European Council.

Mr Johnson appeared to be directly appealing to Arlene Foster’s party at an earlier press conference alongside Mr Juncker, saying the deal allowed the UK to leave the bloc “whole and entire”.

He said the “fair” and “reasonable” agreement would protect the Irish peace process and allow the whole of the UK to take part in new free trade deals.

“I hope very much now, speaking of elected representatives, that my fellow MPs in Westminster do now come together to get Brexit done, to get this excellent deal over the line and deliver Brexit without any more delay,” he added.

The DUP, which has been in close and regular talks with the PM, had criticised his effort for undermining the integrity of the union and being bad for Northern Ireland’s economy.

The deal also “drives a coach and horses” through the Good Friday peace agreement over the issue of consent, a strongly-worded statement from the party said.

“Following confirmation from the Prime Minister that he believes he has secured a ‘great new deal’ with the European Union the Democratic Unionist Party will be unable to support these proposals in Parliament,” it continued.

MPs are expected to hold a meaningful debate on the deal on Saturday after MPs on Thursday approved a motion to hold the first weekend sitting of Parliament in 37 years.

If Parliament does not vote for the agreement on Saturday, the PM faces an almighty clash over whether he will request a further Brexit delay from Brussels as he is compelled to under the Benn Act.

The stance of the DUP is particularly important because the party wields influence over some hardline Tory Brexiteers and Mr Johnson is far short of a majority in Parliament.

Announcing his achievement, the PM tweeted: “We’ve got a great new deal that takes back control, now Parliament should get Brexit done on Saturday so we can move on to other priorities like the cost of living, the NHS, violent crime and our environment.”

He insisted the deal allows the UK to leave the bloc “in two weeks”, just in the nick of time to satisfy his “do or die” commitment to leaving by the current October 31 deadline.

Mr Johnson said that the “anti-democratic” backstop contingency measure to prevent a hard border on the island of Ireland had been abolished.

It proved a major sticking point for his predecessor Theresa May whose deal failed to pass the Commons three times.

“The people of Northern Ireland will be in charge of the laws that they live by, and, unlike the backstop, will have the right to end the special arrangement if they so choose,” the PM added.

But the DUP dug in over the prospect of a customs border between Northern Ireland and the rest of the UK, as well as the issues of consent regarding the suspended Stormont Assembly.

Another issue in the PM’s proposals was whether EU VAT rates would apply in Northern Ireland.

Mr Johnson needs to get a deal approved before the weekend if he is to avoid a major clash over asking for an extension to the current deadline.

The Benn Act passed by no-deal opponents compels him to ask Brussels for a delay to the end of January, but the PM has repeatedly ruled out taking this course of action.

He remains adamant on his stance, with a senior Government official saying the PM’s position is “new deal or no deal, but no delay”.

Getting the new deal approved appears to be an uphill challenge, but the EU’s no-delay threat could force some to back what would now appear to be the final offer.

Jeremy Corbyn was quick to dismiss the PM’s agreement, criticising it for creating a customs border in the Irish sea.

“As it stands we cannot support this deal,” the Labour leader told reporters in Brussels, adding that it did not seem to have the backing of “many of his allies on his own backbenches”.

Mr Corbyn criticised “speculation” when asked about reports that his party could support the deal if it comes with a second referendum.

Nicola Sturgeon also ruled out her MPs in the SNP backing the deal, insisting it will mean Scotland alone is “treated unfairly” when the UK leaves the European Union.

The PM’s spokesman said Mr Johnson plans to hold a meaningful vote on the Withdrawal Agreement and the Political Declaration on Saturday.