The Ulster Unionists have announced their intent to resign from Northern Ireland's power-sharing executive and form an opposition over claims the Provisional IRA still exists.
While the move by the UUP, a minor partner in the five-party mandatory coalition, will not automatically trigger the collapse of the administration it does throw its future into serious doubt, as pressure will now mount on the region's largest party, the Democratic Unionists, to follow suit.
The move comes in the wake of an assessment by the Police Service of Northern Ireland (PSNI) that structures of the supposedly defunct paramilitary organisation are still operating, and some of its members were involved in the murder of Belfast father-of-nine Kevin McGuigan two weeks ago.