DUP leader Arlene Foster has said it is “very important” for the UK to leave the EU by 31 October.
She said there was an opportunity for the new prime minister to “proactively” deal with the backstop.
Mrs Foster said the fact Brexit had not happened yet had caused “discontent within the UK “.
Britain was meant to leave the EU on March 31 but the date was pushed back after parliament failed to back a withdrawal deal.
Speaking at a Policy Exchange event in London on Tuesday, Mrs Foster said she believed Boris Johnson and Jeremy Hunt would both be able to reach a Brexit agreement if they became prime minister.
Mr Johnson and Mr