The Sinn Fein president, Mr Gerry Adams, told a press conference at Stormont yesterday that the political process was now in real crisis.
He said Mr Trimble's claim that Sinn Fein had defaulted on the agreement was wrong. There was no guarantee on decommissioning. "There is no default by Sinn Fein on this issue," he said.
Holding up a copy of the agreement, he added: "That's what people voted for North and South of this island. You show me in this where our party has defaulted. You show me in this where there is a unilateral decision by one party that decommissioning had to be done on their terms by yesterday [Monday, January 31st]."
Mr Adams said he hoped the crisis could be overcome. He repeated the Sinn Fein position that he accepted decommissioning was an obligation under the agreement.
"I've also said I think it can be achieved. I sometimes think the UUP don't want it to be achieved," he added.
Asked about the conviction of the SDLP deputy leader, Mr Seamus Mallon, that there was an understanding that the IRA would decommission, Mr Adams said: "If Seamus Mallon thinks that he can resolve this issue on unionist terms he is welcome to try. If Seamus Mallon thinks that the unionists, not having got it on their terms, are right then to collapse this process then I would be very, very surprised."
Mr Adams said his "certain understanding" was that there was no threat to the IRA ceasefire. He did not know whether the IRA would withdraw from Gen John de Chastelain's decommissioning commission, but he felt the IRA would be unlikely to remain involved if the institutions were suspended.
"Hopefully, if sanity prevails, all of those questions will become academic," Mr Adams said.
The Minister of Education, Mr Martin McGuinness, said that at all times Sinn Fein had been honest in its dealings with Mr Trimble and the other parties. "We have not stepped outside the terms of the agreement. The only people stepping outside the terms of that agreement is the leadership of the Ulster Unionist Party," he said.
The Alliance Party leader, Mr Sean Neeson, said paramilitaries were showing intransigence in the face of a massive popular will for disarmament. "The inaction of both republicans and loyalists now risks fatally undermining the will of the people of Ireland as expressed in referendums North and South," he said.