DUP leader Arlene Foster said talk of a Northern Ireland-only backstop in this week’s Brexit discussions is "far off the mark".
London’s proposed plan would see Northern Ireland remaining in the UK’s customs territory but operating the EU’s rules and procedures on tariffs.
Ms Foster told RTE News: "I think what is important to say is that we do want to get a deal but it has to be a deal that respects the constitutional and economic place of Northern Ireland within the United Kingdom, that there has to be consent.
"There has to be consent which is in accordance with the Belfast agreement in other words there has to be consent from the Nationalist community and the Unionist community," she said.
"And so those things are very important and when I hear talk of the Northern Ireland backstop as I did in your headlines... I think the things are very far off the mark in terms of all of that.
"But it is important that we do work together to get a deal and we will be working certainly with the Government to try and make that happen."
Sinn Fein has called on people to join “widespread demonstrations” against any hardening of the border as a result of Brexit.