The Labour Party has never pretended the Treaty of Nice was perfect but on balance has come down in its favour, the party leader, Mr Ruairi Quinn, said yesterday.
Speaking at the start of the party's referendum campaign, Mr Quinn said the treaty would ultimately advance the cause of peace and stability rather than endanger it. The party has as its campaign slogan "Good for Them, Good for Us".
At each stage of the European integration process, he said, there had been a group of people who had claimed the process harboured doom for Ireland.
"The opposite has been the case," he said. "We have prospered socially, culturally and economically. We should not now deny the same opportunities to the 12 applicant states of central and eastern Europe. To those on the left I would say that the case for solidarity doesn't end at home."
The treaty, he said, was the "imperfect result" of negotiations between 15 states, but the secure future of the applicant states depended on its ratification.
"I would put it to those who seek to pretend that the treaty can be renegotiated that their only allies in Europe are William Hague and his xenophobic Conservative allies."
He said one of the strengths of the Nice Treaty was that it acknowledged there were problems of clarity and under standing within the existing treaties.
Mr Quinn said it should be ensured that whatever position the Government adopted it was one arrived at after comprehensive debate.
Labour is proposing a forum for Irish people to "tease out the issues" and decide where they would like the EU to end up.
The party's MEP, Mr Prionsias De Rossa, said it was essential in the run-up to the next round of treaty negotiations, which may conclude in 2004, that people were fully engaged in the process.
"We have made an innovative proposal for an Irish forum on the future of Europe and we will insist on its establishment in any negotiations we have for participation in government over the next 12 months," said Mr De Rossa, adding that there could be a three-year debate in Ireland which would parallel the debate at European level.
He said enlargement was the bridge between Europe's past and future. "It would be a shame if Ireland were to turn its back on the future having played a significant role over the last quarter of a century in bringing Europe to this historic crossroads."
Labour's spokeswoman on Dublin, Ms Eithne Fitzgerald, said it was taken for granted here that there were working parliamentary institutions and effective public administration, respect for the rule of law, a vibrant civil society and free media.
Broadening membership of the EU had an important role in consolidating peace and democracy on the European continent, she said.
"Ratification of Nice would keep up the momentum for early accession of the first batch of countries and reassure countries further down the accession path that membership is worth working towards and an attainable goal," she said.