DUP leader Peter Robinson has said the Stormont institutions are under threat after the Ardoye return parade on July 12 was banned for a second year.

The First Minister sounded the warning after unionist parties walked out of talks about contentious issues in Northern Ireland, in protest at the Parades Commission decision.

The talks on parades, flags and the past were being held at Stormont as the Commission’s decision was announced.

The Parades Commission banned Ligoniel feeder parade from returning past the Ardoyne shop fronts on the Twelfth evening.

“The institutions have been put under threat by the behaviour of the Parades Commission and those who threaten the Parades Commission,” Mr Robinson said.

“It’s up to us to seek a peaceful response and we trust that, along the line, people will recognise the importance of having respect and tolerance for the cultural expression of our tradition and that violence will no longer be allowed to be the determining factor when decisions are bring taken.”

The DUP, UUP, TUV, PUP and UPRG earloier issued a joint statement over the ban saying it showed that “the commission members place no value on a relationship with unionism and have treated our advice with contempt”.

The discussions, which began on Wednesday, came six months after the last major push to resolve the outstanding issues, the Haass talks, ended without agreement.

Peter Robinson Ardoyne parade ban threatens Stormon

A North South Ministerial Council meeting in Dublin on Friday has been postponed following Thursday’s developments.

Several nights of rioting took place after the same parade was stopped from returning along the road last year, with scores of officers injured.

The road separates unionist and nationalist communities.

The unionist parties said in their joint statement: “The Parades Commission’s determination creates a serious situation for Northern Ireland.

“We know, having seen republican threats of violence being rewarded, the conclusion is swiftly drawn that violence pays.

“We have, for some time, been aware that such an absurd parades determination would bring with it a very real risk of widespread violence and disorder.”

The statement was issued by DUP leader Peter Robinson, UUP leader Mike Nesbitt, TUV leader Jim Allister, PUP leader Billy Hutchinson and Ian McLaughlin of the Ulster Political Research Group.

They said they had “pledged to work collectively on this issue”.

“We do so to avert violence and destruction on our streets with the attendant harm that this would cause to Northern Ireland’s community relations and reputation,” they said.

“If we are to convince unionists that violence is not the only response to those who have consistently succumbed to republican violence and threats of violence, we must provide alternative means to channel justified anger and outrage.

“There will be a graduated unionist response involving the Orange Institution, the PUL (Protestant Unionist Loyalist) community and political unionism. Unionist leaders are willing to share the strain within the political process. Political action in tandem with peaceful and lawful protests is the path we must follow.”

SDLP leader Alasdair McDonnell MP said: “If we’ve learned anything over 40 years, it is that you can make all the threats you like and destabilise things, but at the end of the day you have to come back to the table and you have to do the sane, sensible thing.”

Justice Minister and Alliance Party leader David Ford said: “I have serious concerns that what we are now seeing is the likelihood of a significant increase in tension.

“We’ve already spent over £10m since last July on policing the top of Twaddell Avenue (loyalist protest camp), and that is now likely to increase because of the utterly irresponsible and disgraceful behaviour of the two unionist parties.”