Northern Ireland's five main party leaders discuss flag protests 20 December 2012 Last updated at 17:05 The leaders of the five main political parties are meeting for the first time since the dispute over the flying of the union flag at Belfast City Hall began. The meeting was supposed to take place last week but was cancelled after some parties refused to attend. First Minister Peter Robinson said it was "important that leaders meet when a crisis exists." Mr Robinson met Deputy First Minister Martin McGuinness on Monday. They issued a joint statement calling for the protests to stop. Protests began on 3 December after Belfast City Council voted to fly the flag only on designated days at the city hall. Violence has flared following some of the protests. The first minister said the meeting must result in action. "It can only be useful, in the present context, if action is taken which addresses the flags issue," he said. I will be asking the other leaders to initiate a formal review of the issue of flags and start a public consultation process as part of the review. On Tuesday, Mr Robinson and Ulster Unionist Party leader Mike Nesbitt said they were inviting other unionist politicians and groups to join a forum to address the flags issue. BBC Northern Ireland's political editor Mark Devenport said that both the unionists and nationalists were coming at the issue from different directions. He said that the Alliance Party was of the view that there could be long-term discussions, possibly around a legal mechanism to deal with flags, but that while there is ongoing intimidation they would not be negotiating. "I think they (the leaders) probably know that while they are not going to solve anything today that it would set a very bad image if they came out arguing again," he said. They would be careful I imagine not to engage in any actions that will sort of re-ignite things out on the streets. They will temper their views, but I don't see a solution coming out today.