The SDLP has opened its campaign for a Yes vote in next month's referendum with a strong attack on Sinn Fein, which it accused of "forked-tongue politics" in its approach so far to the agreement.
The SDLP's referendum campaign director, Mr Mark Durkan, called on Sinn Fein to make up its mind on whether it would be supporting the peace deal.
There is speculation that Sinn Fein may call for a Yes vote in the North and a No vote in the Republic in order to appease supporters opposed to changes in Articles 2 and 3.
"Sinn Fein are meant to have left forked-tongue politics behind, but this seems to be a classic piece of forked-tongue politics," Mr Durkan said. "It shows up the shallowness of some Sinn Fein claims that they were the determining influence in this agreement. If Sinn Fein were decisive in terms of the agreement they would now at least be decisive on where they stand."
Mr Durkan predicted an unprecedented turnout in Northern Ireland for the referendum, with a strong majority in favour of a Yes vote.
"I feel confident that the turnout is going to go off the scale compared to other elections. There is unprecedented interest in this campaign among ordinary members of the public. Our phones are hopping with people looking for information on the agreement and how they can vote.
"The SDLP will be turning every stone possible in pursuit of Yes votes. We believe we can ensure that there is a resounding and credible victory." Mr Durkan said the opportunity existed to establish a completely new form of "partnership government" in the North.
"This means nationalists and unionists working together to plan, develop and serve the needs of all the people of Northern Ireland. It will bear no resemblance to the old Stormont regime."
Meanwhile, Mr Alex Attwood of the SDLP has said the RUC must accept change. He was speaking after the RUC Chief Constable, Mr Ronnie Flanagan, made a strong appeal, in an interview in yesterday's Daily Telegraph, for his force to be preserved.
Mr Attwood said Northern Ireland would have a "fundamentally different policing service" if the policing commission was to satisfy its mandate.
Mr Attwood was quoted in the Belfast Telegraph as saying: "The RUC hierarchy should facilitate and encourage change, not resist and deny it.
"The Good Friday agreement lays down the political parameters for policy-making and implementation on a number of areas, including policing, prisoners and decommissioning.
"The institutions of the state, whether it is the bureaucracies or the police will be working within those parameters and that includes Ronnie Flanagan."