The First Minister has used his New Year message to urge flag protesters to be peaceful.
Peter Robinson described the decision to remove the Union flag from Belfast City Hall as "ill-considered and provocative" but said there was no excuse for violence.
"People are entitled, even justified, in protesting but nobody can justify threats, acts of violence or other unlawful behaviour," the DUP leader said.
"Right-thinking unionists will want to channel their opposition to this and similar decisions into political activity aimed at strengthening our British culture and identity."
Mr Robinson spoke of his pride in being British and said that support for the Union in Northern Ireland is "at its highest level". He added: "It is a mark of success for unionism and Northern Ireland that a growing number of Catholics are now content with the constitutional status quo.
"It is our goal to make Northern Ireland a place where people of all backgrounds feel a part."
Meanwhile, Sinn Féin Deputy First Minister Martin McGuinness and SDLP leader Dr Alasdair McDonnell have also both called for peace and a united society in 2013.
Mr McGuinness explained his decision to meet the Queen during her visit to Belfast last year was a "sincere effort" on his behalf to advance reconciliation between republicans and unionists and consolidate the peace process.
"2012 heralded the beginning of a decade of centenary commemorations," he said. "I dearly hope this era will become one in which we at last replace division with new human and political relationships, and forge lasting peace and friendship between our communities, and the islands of Ireland and Britain.
"Our future must be one of reconciliation, and the politics of hope and change."
Mr McGuinness also pledged that Stormont would soon publish the long-delayed Cohesion, Sharing and Integration strategy (CSI) and said that ending "the continuing blight of sectarianism and segregation will require imagination and compromise". Dr McDonnell also alluded to the flags dispute in his message.
The SDLP leader said: "In our divided society, symbols, emblems and issues of identity will remain contentious, ripe for provocation and with the potential to erupt into violent scenes which are beamed around the world unless they are approached from a position of mutual respect and parity of esteem.
"We must demonstrate in every home that devolution delivers for people's needs and people in need."