The DUP have announced that they will not support Theresa May's deal if it is brought back to the Commons.

The party’s deputy leader also ruled out his party abstaining on a meaningful vote. Nigel Dodds tweeted: “The DUP do not abstain on the Union.”

The news comes after Theresa May informed Tory MPs that she would quit if they backed her withdrawal agreement.

READ MORE: Theresa May tells Tories she'll quit if they back her Brexit deal

But DUP leader Arlene Foster said her Brexit deal would endanger the union of the United Kingdom as she made clear her party could still not support Theresa May's Withdrawal Agreement.

The DUP leader told Sky News: "What we can't agree to is something that threatens the union, that has a strategic risk to the union.

"For us in the Democratic Unionist Party, the union will always come first and that has been the issue right from the beginning of all of this."

In a statement explaining the decision, the DUP said: "The DUP and the Government have had good discussions in recent days and some progress on domestic legislation has been made.

"All concerned recognise the need to ensure that as we leave the European Union the economic and constitutional integrity of the United Kingdom is maintained.

"However, given the fact that the necessary changes we seek to the backstop have not been secured between the Government and the European Union, and the remaining and ongoing strategic risk that Northern Ireland would be trapped in backstop arrangements at the end of the implementation period, we will not be supporting the Government if they table a fresh meaningful vote.

"The backstop if operational has the potential to create an internal trade border within the United Kingdom and would cut us off from our main internal market, being Great Britain.

"We want to secure the United Kingdom's departure from, and our future relationship with, the European Union on terms that accord with our key objectives to ensure the integrity of the United Kingdom.

"In our view the current withdrawal agreement does not do so and the backstop, which we warned this Government against from its first inception, poses an unacceptable threat to the integrity of the United Kingdom and will inevitably limit the United Kingdom's ability to negotiate on the type of future relationship with the EU."