The DUP has said it will not take part in any likely review of the Belfast Agreement if the British government does not call fresh elections to the North's Assembly first.
The favoured British response to the crisis is understood to be suspending the Assembly and setting up a review of the agreement. The North's politicians would all be invited to take part.
The DUP's decision not to take part in any such review will put further pressure on Downing Street and the ailing peace process. It is demanding the British government allow the "ordinary citizens of Northern Ireland to speak" by calling an Assembly election before any review.
The party's deputy leader, Mr Peter Robinson told The Irish Times last night: "We would be in a process aimed at patching up what we consider to be a failed process . . . there is no advantage for unionism in the DUP taking part in any review process until after an election."
Britain is understood to be against imminent elections because it believes the DUP would poll strongly, making a deal less likely between the parties.