Sinn Féin leader Mr Gerry Adams has said "anti-republican" elements in Dublin and London have tried to devalue and frustrate Sinn Féin's contribution and IRA initiatives in the peace process.
The Irish and British governments are aiming to begin a review of the Belfast Agreement in the last week of January - possibly the 29th.
All the North's parties have now responded to the letter of invitation sent by the two governments at the beginning of December and have outlined their positions.
Delivering a keynote address ahead of the review, Mr Adams commended the Taoiseach and the British Prime Minister for starting a process of change five years ago, but he urged the two leaders to spearhead a pro-Agreement strategy, and make it clear to those who were trying to wreck the accord they would not succeed.
"With the application of proper strategies and political will I believe the process can be moved on," he said.
"However if the next five years is to be a continuation of the past five years, then we face continuous stalemate, stagnation and eventual breakdown. No political process could be sustained on such a diet," Mr Adams said.
"As the leaders of the two sovereign governments and the joint and co-equal guarantors of the Agreement, it falls to them [Mr Blair and Mr Ahern] to marshal the pro-Agreement forces and implement a strategy to defeat the wreckers and move the process forward.
"This may mean the pro-Agreement, pro-peace parties and governments agreeing and setting out an agenda for progress. Obviously such a task is outside the remit of the review and may require a different mechanism."
Mr Adams said London and Dublin would also have to honour their pledges on police reform, the scaling down of the British army presence, the return of paramilitaries who have been on the run, addressing concerns about the Equality and Human Rights Commissions, the status of the Irish language and allowing people in Northern Ireland to participate in political structures south of the border.
The West Belfast MP acknowledged republicans were "not exempt from criticism" but he hit out at those who had focused solely on IRA arms and not on the weapons of "unionist paramilitaries and British state forces".
Mr Adams also said the Dr Ian Paisley's Democratic Unionist Party can be moved to a position of accommodation with republicans.
But he said the governments could not afford to wait for the DUP and should press ahead with commitments made in the process over the past five years.
"There is no doubt that unionism, even of the Paisleyite kind, will have to face in time the same reality that led the Ulster Unionist Party to agree the Good Friday Agreement. But this will take too long and the process of change and the rights of citizens cannot wait. The two governments have to face up to that reality."
Additional reporting PA
