The ratification of the Nice Treaty was not necessary and enlargement of the European Union could go ahead without it, a Danish Euro-sceptic MEP told the National Forum on Europe in Dublin Castle.
Mr Jens-Peter Bonde said the countries applying for EU membership could have their voting strength in the Council of Ministers and their representation in the European Parliament moved from the Nice Declaration to their individual treaties of accession.
As things stood, five countries could join the EU on the basis of the Amsterdam Treaty without any institutional change.
"Objectively, there is no need to ratify the Treaty of Nice. What is needed to provide for enlargement can be put in the accession treaties. What is bad can then be forgotten."
He believed future historians would regard the Irish "No" to Nice as "the healthy warning which led prime ministers and presidents to realise that the next treaty should be produced in a different, more transparent and involving way".
Highlighting the "democratic deficit" in the EU, he continued: "The regular EU practice today is that laws are made by bureaucrats in rooms where the elected members of parliament have no say."
The summit in Laeken on December 14th would call for a convention to prepare the next EU treaty. He said the convention should be instructed to prepare two options to go for referendum in all member-states.
The federalists could propose a European constitution overruling national constitutions and supreme courts as well as the European Court of Human Rights in Strasbourg.
"The alternative proposal could be a draft agreement between sovereign nation-states controlled by their national parliaments and sharing laws and law-making capacity only in clearly-defined cross-border matters where none of us has anything to lose but much to win," Mr Bonde said.
Mgr Brendan Devlin, on behalf of the Catholic Bishops' Conference, warmly welcomed the forum as an exercise in participatory democracy. The bishops supported EU enlargement as part of the process of achieving the European ideal, the basic principles of which shared "common ground with many preoccupations of Catholic Christianity".
He said: "The bishops would naturally share the popular concern on such issues as sovereignty, neutrality and militarisation, on a charter of rights, on the democratic deficit and popular alienation.
"These topics will undoubtedly be addressed at future sessions which will, we may hope, lay to rest certain bogeymen, if such they are, like the vast Brussels bureaucracy, or the EU as an authoritarian and elitist system dedicated to wiping out national or individual preferences."
Mr Andrew O'Rourke, from the Institute of European Affairs, said that, after the Nice referendum, the candidate countries had expressed "disappointment, puzzlement, sadness and above all concern that their membership may be delayed".
They could do without further uncertainty and delay. "They now hope that whatever problems Ireland has with European integration can be resolved without adding to the huge problems they themselves have with some success been trying to deal with," Mr O'Rourke said.
Ms Maria Cronin, of the employers' organisation IBEC, said Ireland should be at the forefront in promoting a spirit of generosity in welcoming new member-states to the EU. "We would hate to think what would be the negative impact on the political and economic development of these, mostly young, democracies if Irish and EU public opinion was to deny them the opportunity of membership."
Mr Roger Cole, of the Peace and Neutrality Alliance, said his organisation was opposed to the "desire of the elite to destroy neutrality". He called for a protocol to exclude this State from the "European army", otherwise known as the Rapid Reaction Force (RRF).
The war that began in Afghanistan was going to go "on and on" and would involve Ireland and other EU states, he said.