Politicians must have the courage to put the most challenging issues at the centre of the negotiations, church leaders warned.
Peace process gains of recent years should not be taken for granted, the heads of the Catholic, Church of Ireland, Methodist and Presbyterian congregations urged in a joint statement.
They said the achievements of Northern Ireland's peace process should be protected.
"Not everything in this vision has yet been achieved as many of us had hoped, but the current circumstances provide an opportunity for each one of us to ask ourselves what we are doing to make it a reality and whether we have, perhaps, begun to take the progress of recent years for granted," the statement said.
"In any process of conflict resolution, we should be prepared to face setbacks and embrace these challenges as an opportunity to continue to learn from our mistakes, while working to put in place the necessary safeguards.
"A culture of blame will only trap us in an endless cycle of instability and insecurity."
The joint-statement was issued by Archbishop Richard Clarke, Church of Ireland Archbishop of Armagh; Archbishop Eamon Martin, Catholic Archbishop of Armagh; Bishop John McDowell, President of the Irish Council of Churches; Rev Bill Mullally, President of the Methodist Church in Ireland and Rt. Rev Dr Frank Sellar, Moderator of the Presbyterian Church in Ireland.
It added: "Our elected representatives need our support if they are to have the courage to put the most challenging issues at the centre of the current negotiations and take responsibility for finding lasting solutions.
"As Christians, we recognise the importance of supporting those in positions of political leadership through prayer and action."
