The SDLP leader, Mr Mark Durkan, has written to the leaders of all the pro-agreement parties urging them to formulate a co-ordinated approach to the New Year review of the Belfast Agreement.
As all the Northern parties prepare to submit their end-of-year proposals on how the review should be organised, Mr Durkan called on pro-agreement parties to meet in early January to agree a unified position on the review.
"In the last 5½ years what hurt the agreement most was not the attacks on it by anti-agreement elements. Instead, what damaged it deepest was the inability of pro-agreement parties to work together and settle their divisions," he said.
"We must learn from these mistakes. Pro-agreement parties need to stand up together for the agreement and live up together to all its requirements. In this review only those who want to destroy the agreement will benefit if there is no solidarity among pro-agreement parties."
The SDLP leader issued his call as a strengthened DUP continued to insist that the review must amount to a renegotiation of the Belfast Agreement. His appeal also comes as former Ulster Unionist MLAs Mr Jeffrey Donaldson, Ms Arlene Foster and Ms Norah Beare continue their negotiations with the DUP on whether they should join the Rev Ian Paisley's party, which would further increase the DUP's bargaining position.
Meanwhile, the Northern Secretary, Mr Paul Murphy, said in his Christmas message that as he looked back over 2003 it would be easy to be frustrated at the twists and turns of the political process. For the sake of the victims of violence it was vital that Northern Ireland never returned to the "dark days".
"Of course I am disappointed that we do not yet have an assembly up and running, with local politicians making the decisions which affect local people. But my overwhelming feeling is still one of gratitude. I am grateful that every year Northern Ireland becomes a better, safer place," he added.
"Ten years ago, when I first became involved with Northern Ireland, Christmas shopping in Belfast was a very different experience. There was always the fear of violence. Today our town centres have become normal and for the first time in a generation Northern Ireland enjoyed a summer as it should be.
"I take none of this for granted and I know that there is more to do. And I know that for the many victims of violence I have met during the year Christmas is a particularly painful time. We owe it to them to be resolute in our determination that we will never return to the dark days of conflict. We owe it to them to ensure that we continue to build a brighter future for the generations to come," said Mr Murphy.