The country's largest trade union, Siptu, has said it is in favour of the ratification of the Lisbon Treaty.
Following a meeting of its national executive council this afternoon Siptu president Jack O'Connor said that on balance ratification of the Treaty was in the best interest of working people and their families.
However the union said it "harboured a number of reservations" about the treaty.
The union said that it was "particularly dissatisfied" that the European Trade Union Confederation's proposal for a social progress protocol which would have addressed many of its concerns had not been acted upon.
"However, in our analysis we are satisfied that the ratification of the treaty, (including the Charter of Fundamental Rights), would not make matters worse overall. Indeed, it has the potential to improve them," it stated.
Mr O'Connor said that while Siptu would engage in the debate on Lisbon it would not be sharing platforms with the representatives of the Government parties.
The union said that its agenda was not the same as that of the Government parties.
In the previous referendum on Lisbon Siptu withheld backing the treaty in the hope that it could persuade the Government to legislate for an entitlement for collective bargaining. However the Government refused to do this and said the issue should be dealt with in the social partnership process.
However Mr O'Connor said that what had changed in the interim was that the Labour Party had undertaken to legislate on collective bargaining rights. He said the Labour Party now had a reasonable prospect of being a significant player in the formation of the next Government.
In a statement Siptu said that until 2004, the experience since Ireland became a member of the EEC (as it was then known) in 1973 was almost universally positive. It said living standards, people's rights at work and equality legislation improved dramatically.
However it said that since then the picture had not been so universally positive. It said that in the past few years, there had been a noticeable drift towards strident free-marketeerism.
"This has been reflected in a number of initiatives at the level of the EU Commission and judgements issued by the European Court of Justice (ECJ) on matters affecting workers' rights."
Siptu said claims that a 'Yes' vote in the referendum would result in the minimum wage being reduced to €1.84 per week, that Turkey would automatically be admitted to the EU, or that young people could be conscripted into a European Army were "absolute nonsense".
However it said that on the other hand, so also were the assertions that the treaty was the best thing that ever happened or that it would be the end of the world if the country voted 'No'. It said the issues at stake were much more subtle.
Siptu said trade unionists on the 'No' side hoped that rejection would stop the project or perhaps result in a better treaty.
"Nothing is impossible, but in our view this is very unlikely. We must also take account of the current balance of forces in the political arena. Twenty-three countries have ratified already and the remaining three others, apart from ourselves, have resolved to do so."
"It is not simply a case of saying 'No' this time and waiting for a better outcome. We must also take account of the possibility of worse emerging," Siptu said.