A Northern Ireland MP was suspended from the House of Commons and a recall of the region's Assembly urged as unionist anger intensified over a decision to ban an Orange Order parade past a sectarian flash point.
Democratic Unionist Nigel Dodds was ordered to leave the chamber after he accused Northern Ireland Secretary Theresa Villiers of giving a "deliberately deceptive" answer about the controversial July 12 event in his North Belfast constituency.
While Orangemen will march past the Ardoyne shops on the Crumlin Road on Friday morning on their way to the annual Twelfth demonstration, the Parades Commission adjudication body has banned them from taking the same route on their return journey in the afternoon.
The interface area has been the scene of serious rioting on the Twelfth in recent years.
"In light of the determination issued by the Parades Commission last evening it is right and proper that these issues should be debated at an appropriate time next week in the Assembly to allow for the expression of opposition to a decision which many see as rewarding riotous behaviour by dissident republicans last July," said a party statement.
The Orange Order has branded the commission's decision "ludicrous" but urged supporters not to react with violence.
The DUP deputy leader said that when he had asked a question earlier to Ms Villiers during Northern Ireland Questions she had failed to address the issue of her powers to overrule the Parades Commission's decision to ban the Orange parade.
"I have to say that in my view that was deliberately deceptive and I think that was absolutely outrageous and will not go down well in terms of people back home," he said.