The remaining members of the Ulster Unionist Party delegation have left the talks aimed at saving the Good Friday Agreement.
The discussions at a hotel in Staffordshire in the English midlands, have so far failed to find agreement among the pro-Agreement parties.
The atmosphere at the talks has been described as grim.
Earlier the Ulster Unionist leader, David Trimble, left the negotiations to attend another engagement.
It is expected the talks will break up to allow unionists celebrate the Twelfth of July, and the meeting will reconvene on Friday.