The Nice Treaty would lead to "widespread privatisation" of public services such as education, hospital and other health services, water supply and refuse disposal, according to a new organisation, Trade Unionists Against Nice, launched in Dublin yesterday.
The group's chief spokesman, former regional secretary of the ATGWU, Mr Mick O'Reilly, said Article 133 of the treaty would bring about "privatisation by the back door".
"Nice is in effect a framework for a massive privatisation programme, which will result in Irish workers paying more for run-down public services. Is it any wonder that the business community have never before spent so much money advocating a Yes vote?" he said.
Holding a second referendum a year later was "an affront to democracy", as it was exactly the same treaty, he added.
"This treaty serves the selfish and profiteering interests of large international corporations which is why trade unionists will vigorously campaign for its defeat - again," he said.
He also warned about the "militarisation" of the European Union. "We are being salami-sliced into a European army," Mr O'Reilly said.
The group criticised the executive of the Irish Congress of Trade Unions (ICTU) for backing the treaty.
"They are undemocratically urging a Yes vote, without any mandate or consultation with members of constituent unions on an issue whose potential importance far exceeds that of any social partnership agreement."
Mr Finian McGrath TD, a member of the Irish National Teachers' Organisation (INTO), said the treaty would lead to "large-scale privatisation". He was particularly angry at what he termed the "lack of leadership" on this issue from the ICTU.
Meanwhile, the Green Party has accused the director of the Progressive Democrats' campaign, Mr Tom Parlon - who is also Minister of State at the Department of Finance - of making "the most stupid statement" of the referendum campaign.
Responding to Mr Parlon's claim that, under the Green Party, Ireland's only sustainable crop would be "tumbleweeds", Mr Trevor Sargent said it showed that the Government was "in a panic" and could think of no convincing reason for farmers to vote Yes.
The Green Party leader added: "Tumbleweed is a symbol of the US dust-bowls of the 1930s which, ironically, would not have happened if Green Party policies of focusing on the viability of family farms and the health of the soil had been followed."