The North's First Minister, Mr David Trimble, has insisted that the Ulster Unionist Party remains committed to the Belfast Agreement. He has also accused nationalists of adopting a "hysterical reaction" to the Ulster Unionist Council motion threatening to collapse the Executive.
In the face of criticisms from the SDLP and Sinn Féin leaders Mr Gerry Adams and Mr Mark Durkan that Ulster Unionists were now anti-agreement, Mr Trimble said the "Belfast Agreement was still the best chance for a generation and that the UUP were still committed to it".
Despite the UUC ultimatum, the British and Irish governments and Sinn Féin and the SDLP had it in their gift to avoid a political crisis, said Mr Trimble in speeches at the Labour Party conference fringe in Blackpool yesterday and in east Belfast on Tuesday night.
"Nationalists need to assess the political situation calmly rather than pander to republicanism in their analysis," he said.
"Credibility in the process has to be restored. We need a security response to the disgraceful loyalist violence but furthermore we need a wholescale attitude change on the part of nationalist Ireland, particularly Sinn Féin/IRA if they want to build peace with unionism," he added.
Mr Trimble said the agreement had to be fully implemented and "that continued paramilitarism, whether in Colombia, the Castlereagh raid or the Belfast interfaces had a destabilising effect".
Citing Sunday's shooting of a bus driver in Derry, he said that the IRA were still involved in violence. He accused republicans of trying to "silence" locals from speaking out against intimidation in Derry.
"It is precisely this sort of behaviour that the government has tolerated and it is this sort of behaviour which has caused the crisis we are in. What the Ulster Unionist Council has done is offer a wake-up call to London, Dublin and nationalism," he said.
"We have given them a chance to get it fixed. They were going to sleep-walk us into another disaster next spring but for the actions of our party. We expected that call to be a surprise - that's the whole point of a wake-up call."
He was critical of nationalists and Deputy First Minister Mr Durkan, in particular, who in Blackpool earlier this week said unionists were ignoring loyalist violence.
"We are really disappointed with the attitude of nationalists, who have shown no signs of thinking about the situation that we are in. I am disappointed in the reported comments of Mark Durkan here in Blackpool this week.
"It was sad that he alleged that the UUC didn't address the issue of loyalist violence.
"He obviously hasn't read our resolution. It is even sadder that he appears not to have responded to an IRA attack in his own constituency.
"It is ironic that he falsely accuses us of selective condemnation when he averts his gaze from incidents on his own doorstep." Meanwhile, Sinn Féin vice president, Mr Pat Doherty, called on the British government to make it clear to unionists that implementation of the Belfast Agreement will proceed.
"The Good Friday agreement is a binding international agreement between the Irish and British governments. They are obliged to implement the agreement and have a joint and co-equal responsibility for the implementation of its terms," he said in Blackpool before meeting Northern Secretary Dr John Reid yesterday.
"The process must be moved forward through resolute and speedy action by both governments, but particularly the British government," added Mr Doherty.