The Irish and British governments have made it clear the Belfast Agreement is not negotiable, the Minister for Foreign Affairs told the Dáil.
Mr Cowen said he wanted to state firmly that its core values must be at the heart of any stable dispensation for the future.
"I cannot imagine any nationalist of any persuasion or, indeed, any Irish government, being willing to dilute the key protections and principles at the heart of the agreement," he added. "Those who argue that the agreement must be renegotiated to secure the majority support of unionists, which they allege is in deficit, have never clarified who they expect their negotiating partners to be or why a solemn referendum, in both parts of the island, should be overturned." Mr Cowen was speaking during a debate on a Sinn Féin Private Members' motion deploring the British government's decision to cancel the Assembly elections due to be held tomorrow. The motion, which will be voted on tonight, also calls for representation in the Dáil for Northern representatives.
The reality for unionism, said Mr Cowen, must be that devolved government would only be available in the context of the kind of balanced political arrangements contained in the agreement.
The reality for nationalism, said Mr Cowen, was that sustainable participation by republicans in such an inclusive administration required the cessations of all paramilitary activity, as outlined in the Joint Declaration itself. "In the absence of that, there is little prospect of unionist partnership in government on a stable and sustainable basis."
Mr Cowen said he noted that the UUP MP, Mr Jeffrey Donaldson, was recently reported as calling for an unequivocal rejection of the Joint Declaration. A rejection of the declaration might have more to do "with the political fault-lines between nationalism and unionism, or, indeed, within unionism itself". If so, "it is a particularly dismal manifestation of the zero-sum mindset that we are trying to leave behind".
Mr Aengus Ó Snodaigh (SF, Dublin South Central) said the British government had unilaterally suspended the democratic institutions established under the agreement. It had also cancelled elections in the North, and there was no guarantee when they would take place.
"The British government has no right to cancel elections in Ireland, which derive directly from the Good Friday agreement and the endorsement of that agreement by the overwhelming majority of the Irish people."
Mr Martin Ferris (SF, Kerry North) said many Northern nationalists were becoming increasingly disillusioned with the "so-called democratic process".
Mr Ferris said: "I don't need to rehearse the arguments here today, but it must be remembered that the nationalist-republican population of the Six Counties never asked to be part of that statelet. They never asked to be abandoned by successive Irish governments. They never asked to be treated as second-class citizens in their own country. It was something foisted upon them without even the slightest reference to their consent - and they were left to struggle on their own in the situation in which they found themselves.
"They were at best ignored and disenfranchised by the British state in terms of social and economic opportunities, and at worst considered a threat to unionist dominance ."
The Fine Gael leader, Mr Enda Kenny, called on the two governments to convene, with a new urgency, round-table talks with all the pro-agreement parties. "The documents from all sides are now in the public domain," he added. "Then let their authors sit down to sort out what still divides them, once and for all. To do less will, ultimately, prove a false choice." There was a gap which had to be breached for lasting peace on the island. "And Sinn Féin and the IRA can bridge that gap by giving us clarity."
