EU leaders have left open the option of extending Brexit beyond 31 October if the new deal is voted down by the Commons, in a blow to Boris Johnson’s strategy.

The prime minister had been seeking to pitch Saturday’s vote in the Commons as a choice between deal or no deal after coming to an agreement with the EU.

Johnson was helped by comments from Jean-Claude Juncker casting doubt on the possibility of a further Brexit delay, but the heads of state and government did not follow the European commission president’s lead.

A summit communique issued after two hours of discussion tasked the commission and European parliament with taking “the necessary steps to ensure that the agreement can enter into force on November 1”.

But a senior EU official said that the leaders would follow events on Saturday, and reflect on the next steps if they were in a “different situation”.

A second diplomatic source said they had chosen not to interfere in a “sensitive domestic debate … but they leave the door open to the possibility of an extension, to be discussed at a later stage – if required”.

Donald Tusk, the president of the European council who will provide guidance on the options in the event of another rejection of a deal, said the issue of an extension was for a later date.



“Our intention is to work towards ratification. We support a deal and this was a clear decision of the 27 member states. And we prepared for this ratification, politically logistically, technically”, Tusk said. “Now the ball is in the court of the UK. I have no idea what will be the result of the debate in the House of Commons on Saturday. It isn’t for me to comment on political developments in the UK. But if there is a request for an extension, I will consult member states to see how they react.”

Play Video 0:38 'It has to be now': Jean-Claude Juncker claims EU won't further delay Brexit - video

Johnson is facing an uphill battle to build a majority after the Northern Irish Democratic Unionist party rejected the revised deal, describing it as driving “a coach and horses through the professed sanctity of the Belfast agreement”.

Juncker had tried to help sell the deal by pouring doubt on a further Brexit extension in the event of it being rejected.

He told reporters he was “ruling out” a prolongation, but the issue is solely the remit of the EU heads of state and government. “If we have a deal, we have a deal and there is no need for prolongation,” he added

No other EU leader expressed the same view. One senior EU official told the Guardian of Juncker’s intervention: “It is fake news.”

Agreement on the new deal was struck in a phone call between Juncker and Johnson at 11.10am London time.

During a later joint appearance they called on the Commons to pass the deal so that negotiations could move on to the terms of the trading relationship.

Play Video 'A very good deal': Johnson and Juncker announce new Brexit agreement – video

Johnson said: “I hope very much … that my fellow MPs in Westminster do now come together to get Brexit done, to get this excellent deal over the line and to deliver Brexit without any more delay so that we can focus on the priorities of the British people.”

Juncker said the EU would ensure the UK was able to exit on 31 October if parliament gave its consent to the deal on its “super Saturday” sitting this weekend.

Johnson will have to win over a significant number of Labour MPs and some of the 21 former Conservatives who had the whip removed last month.

As details of the new deal emerged, the DUP issued a statement attacking Downing Street’s deal. “It is our view that these arrangements would not be in Northern Ireland’s long-term interests,” the party said. “Saturday’s vote in parliament on the proposals will only be the start of a long process to get any withdrawal agreement bill through the House of Commons.”

Corbyn refuses to confirm backing for second referendum on Johnson's deal Read more

Soon after the agreement was announced, the Labour leader, Jeremy Corbyn, also rejected it as worse than the deal produced by Johnson’s predecessor in Downing Street Theresa May.

The EU’s chief negotiator, Michel Barnier, said the prime minister had backed himself to win over a majority of MPs to support the deal during a phone call earlier in the day with Juncker – but he adopted a sceptical tone.

“[Boris Johnson] said, based on this agreement and the explanations he intends to give, he has the confidence to win that vote,” Barnier said. “That is all I can say on that.”

Quick guide Why is the Irish border a stumbling block for Brexit? Show Hide Counties and customs Inside the EU, both Ireland and Northern Ireland are part of the single market and customs union so share the same regulations and standards, allowing a soft or invisible border between the two.

Britain’s exit from the EU – taking Northern Ireland with it – risks a return to a hard or policed border. The only way to avoid this post-Brexit is for regulations on both sides to remain more or less the same in key areas including food, animal welfare, medicines and product safety. The 'backstop' in Theresa May's Withdrawal Agreement was intended to address this - stating that if no future trade agreement could be reached between the EU and the UK, then rules and regulations would stay as they are. This has been rejected by Brexit supporters as a 'trap' to keep the UK in the EU's customs union, which would prevent the UK striking its own independent trade deals. There are an estimated 72m road vehicle crossings a year between Northern Ireland and the Republic of Ireland, and about 14% of those crossings are consignments of goods, some of which may cross the border several times before they reach a consumer. Brexit supporters say this can be managed by doing checks on goods away from the border, but critics say it will be difficult to police this without any physical infrastructure like border posts or cameras, which could raise tensions in the divided communities of Ireland.

Interactive: A typical hour in the life of the Irish border Photograph: Design Pics Inc/Design Pics RF

Asked whether the agreement was the final possible deal for the EU, he declined to comment.

Under the agreement, Barnier said, Northern Ireland would stay in the EU’s single market for goods and the EU’s customs code would be enforced on goods coming from Great Britain into Northern Ireland.

“This means that all applicable procedures on goods will take place at points on entry into Northern Ireland and not across the island,” he said.

But Northern Ireland would legally remain in the UK’s customs territory, to allow the prime minister to boast the country “whole and entire” had left the EU.

Barnier said: “It will therefore benefit from the UK future trade policy. But Northern Ireland will also remain an entry point into our single market. So what have we done to square this circle? UK authorities can apply UK tariffs on products coming from third countries as long as those goods entering Northern Ireland are not at risk of entering our single market. However, for goods at risk of entering the single market the UK authorities will apply the EU tariffs.”

Businesses in Northern Ireland will be able to apply for rebates if the UK has lower tariff rates on goods imported from outside the EU.

The new Irish protocol also includes a last-minute compromise on VAT, after negotiators worked through the night to resolve this final sticking point. The UK has now conceded that Northern Ireland will follow EU rules on VAT, although the UK will remain responsible for collecting VAT and enforcement action. A joint committee of EU and UK officials will oversee how the system works.

Facebook Twitter Pinterest The Labour leader, Jeremy Corbyn, said Boris Johnson had negotiated an even worse Brexit deal than Theresa May’s. Photograph: Sean Gallup/Getty Images

Under a complicated consent mechanism, four years after the end of the transition period, the Northern Ireland assembly at Stormont would vote on maintaining the arrangements.

The assembly would have to decide whether to vote by a simple majority or under a vote in which 40% of both nationalist and unionist assembly members would be required to give their assent. A 60% threshold of all members would need to be passed in that case. If Stormont was not sitting, the status quo would continue.

There would be another opportunity four years later to give consent if they voted by simple majority, and eight years later if they took the cross-party route. A two-year notice period would be granted if Northern Ireland exited the special relationship with the EU to allow alternative arrangements to be put in place.

“This democratic support is a cornerstone of our newly agreed approach,” Barnier said. “Why? Because this newly agreed protocol is no longer to be replaced by a subsequent agreement between the EU and the UK.”

Barnier said Johnson had agreed the political declaration would maintain British commitments to fair competition. The prime minister had agreed this was the quid pro quo for a free-trade agreement which would seek to keep trade between the UK and the EU free of tariffs and quotas.

The EU negotiator said the British government was seeking a looser relationship to the bloc and “the option of creating a single customs territory between us has been discarded”.