The Democratic Unionist party is threatening to scupper the Brexit deal that Boris Johnson is on the brink of agreeing with the EU.

On the morning of a crucial EU summit in Brussels, a joint statement from the DUP’s leader, Arlene Foster, and her deputy, Nigel Dodds, explicitly says the party cannot support the deal that is close to being finalised.

Quick Guide Why is the Irish border a stumbling block for Brexit? Show 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

The pound fell 0.5% against the dollar and the euro within minutes of the announcement.

The DUP statement said: “As things stand, we could not support what is being suggested on customs and consent issues, and there is a lack of clarity on VAT.”

The statement will come as blow to the prime minister, who hopes to bring back a deal from the Brussels meeting and then secure the backing of parliament in a rare Commons vote pencilled in for Saturday.

The backing of the 10 DUP MPs is crucial for the success of that vote because many Conservative Brexiters have indicated they will not back a deal that is opposed by unionists.

Steve Baker, the chair of the hard Brexit European Research Group, said he was optimistic the group would back a deal. But he also suggested the ERG could not support it if Johnson failed to secure the backing of the DUP.

“If the DUP are happy, it’s not for us to gainsay” @SteveBakerHW confirms that the ERG will take their lead from the DUP on Northern Ireland. #Peston pic.twitter.com/RpQri2fY24 — Peston (@itvpeston) October 16, 2019

The DUP statement added: “We will continue to work with the government to try and get a sensible deal that works for Northern Ireland and protects the economic and constitutional integrity of the United Kingdom.”

Johnson has met Foster and Dodds three times in the last three days as he tried to shore up their support before Saturday’s deadline to prevent a delay to Brexit.

Q&A What is the European Research Group (ERG)? Show The European Research Group (ERG) is a research support group for Conservative MPs who oppose the UK's membership of the European Union. It was formed in 1993 as a response to the Maastricht Treaty which reformed the European Economic Community as the European Community. The group is part-funded by subscriptions paid out of MPs’ parliamentary expenses, and is currently chaired by MP Steve Baker, with Mark Francois as his deputy. Jacob Rees-Mogg was previously chair. The group publishes research and reports on the UK's membership of the EU, although it is secretive about its work, and does not even issue a list of members.

Jean-Claude Juncker, the European commission president, told Johnson in a phone call on Thursday morning that time was short if leaders were to approve the Brexit deal this week.

A spokesman for the commission said: “Every hour and minute counts before the [European council],. We want a deal.”

EU leaders are meeting in Brussels in the afternoon for a two- day summit and Brexit was due to be the first item on the agenda.

A senior EU official said a legal text was yet to be shared among member states as Downing Street had not given the green light. “Maybe we have a deal, maybe not”, the official said. “We have somehow got used to it – we know when Brexit is on the agenda we expect the unexpected.”

Discussions on the tentative Brexit deal could now be pushed back to Friday to give Johnson more time to win over the DUP.

The official said: “Still today we don’t know how things will evolve. But I think at a certain moment, if there is no legal text there will be someone who will say: ‘A withdrawal agreement is an international treaty and my officials need to read it before I approve it – this is an ancient tradition and I am not willing to change it’.”

Johnson would be given an opportunity to address the EU27 on the terms of the deal, if it was secured, the source said. “We will have to consider our options in light of the situation”, the official said in an acknowledgement that the issue of a Brexit extension beyond 31 October was likely to be discussed.

The official said even if a deal was given political approval at the summit, it “may be impossible” to have it ratified before 31 October, given the complexity of the treaty, the need for “legal scrubbing” and parliamentary scrutiny on both sides of the channel.

The housing secretary, Robert Jenrick, said on BBC Breakfast: “We know there are clearly concerns on the part of the DUP and we want to try and work through these productively in the hours to come.

“All sides in this do want to secure an orderly exit from the EU, and I think one is in sight, although there is clearly very significant issues to be hammered out. Let’s wait and see.”

He said he expected Johnson to go to Brussels to meet with members of the European council.

Under the so-called Benn act, if Johnson cannot get a deal passed by Saturday he will be forced to seek an extension to the 31 October deadline for the UK to leave the European Union.

The DUP is digging 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 significant issue is whether EU VAT rates would apply in Northern Ireland.





Johnson told the 1922 Committee of Tory backbenchers a day before the summit that his situation was like climbing Mount Everest, according to MPs in attendance.

The Brexit secretary, Stephen Barclay, has confirmed that the PM will write a letter asking for an article 50 extension if no deal is in place by Saturday.

This is despite Johnson repeatedly ruling out asking for a further delay under his “do or die” commitment to leave the EU by the current Halloween deadline.