THE DUP has confirmed it will not support Boris Johnson's Brexit deal in a House of Commons vote.

The party's 10 MPs will vote against the Prime Minister, citing issues with customs and consent issues.

A statement from DUP leader Arlene Foster and deputy leader Nigel Dodds said: "We have been involved in ongoing discussions with the Government.

"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.

"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."

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The pound fell 0.5% against the dollar and the euro within minutes of the announcement by the DUP that the party cannot support the Brexit deal as it currently stands.

A pound was worth 1.2759 dollars and 1.1525 euros.

Tory MP and Housing Secretary Robert Jenrick said: "We always knew these negotiations were going to be difficult and we're going to go down to the line.

"We're working very intensively... to try and secure a deal."

Asked whether the Prime Minister would meet with the DUP today, Jenrick said: "I don't know the exact arrangements for the next few hours, but be assured the Prime Minister and his team are in intensive negotiations with all parties, including with the DUP.

"We want to provide sufficient comfort for the DUP and unionists in Northern Ireland to feel that the arrangements we would put in place with this deal are sufficient to give them comfort to support it."

Jenrick added: "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 the PM to go to Brussels to meet with members of the European Council.

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The man set to become the next leader of the Ulster Unionist Party has signalled that he would adopt a pro-Remain position.

Steven Aiken, who is the only candidate declared in the contest to replace outgoing Robin Swann, said Johnson's proposed deal would be worse than a hard Brexit for the region.

His comments mark a potentially significant shift for the UUP, and would create clear blue water between its position and that of its Brexiteer Unionist rivals the DUP.

The UUP campaigned for Remain in the referendum but, after the result, subsequently advocated for leaving with a deal, insisting the 2016 vote had to be respected.

Aiken told the Nolan Show on BBC Radio Ulster: "This has been a disaster for Northern Ireland, the only way we can really get out of this is to stay.

"For people in Northern Ireland it is very clear – Boris Johnson's deal is bad for us, the best thing for us in many respects is to stay in."

Aiken claimed the DUP was undermining the Union.

"I am very, very clear that what the DUP have been doing has been detrimental to the future of Northern Ireland and detrimental to the future of the Union," he said.

"Anybody who believes that putting a border down the Irish Sea isn't severely impacting the Union, I am telling you right now you've really got to ask yourself what their commitment is to the future.

"As far as I am concerned the Union is the most important thing."

Aiken said remaining in the EU could save the Union and prevent a united Ireland.

"There is no doubt whatsoever that if we remain within the EU that many of the questions that are being asked now about the future of Northern Ireland would be taken off the table and actually we could get down to what we really want to do, which is making Northern Ireland work again," he said.

Aiken said he had consulted widely with the party membership before declaring his pro-Remain position.

"If I become the leader of the Ulster Unionist Party and I am duly elected and we've gone through all the process that is the mandate I am standing on," he said.

"And that's the mandate we need to have to make Northern Ireland work again because Northern Ireland businesses, Northern Ireland people need certainty and right now there is no certainty whatsoever."

He said his preference would be for a Brexit deal that had no barriers to trade with the EU and within the UK, but he said that was not on the table.