Up to 10,000 people marched on the Dáil today in protest at the controversial plan by Irish Ferries to lay off hundreds of unionised seafarers and replace them with cheaper labour from eastern Europe.
Siptu president Jack O'Connor said the large number of protesters was "an indication of the depth of feeling around the issue".
Mr O'Connor told the rally that workers appreciated the issues of "displacement and exploitation" involved.
He criticised the proposed EU services directive that will let businesses sell services in other EU states without having to adapt to their labour legislation.
Mr O'Connor told ireland.comthe directive would allow employers "to transport workers from one end of the EU to the other and impose the 'going rate' in the member state with the poorest conditions applicable."
He said that the Irish Ferries dispute was significant because "it is the highest profile and most blatant example of that trend".
"This directive could undermine the entire EU project," he added. "It's as big as that."
Leaders of the 15 largest trade unions in the State joined in today's march to Leinster House.
Irish Ferries Chief Officer Noel Fagan with his four-year-old daughter Alannah. Photo: Barry Malone
Ictu general secretary David Begg warned: "A race to the bottom in employment conditions will almost certainly create social tension and a misjudged antipathy to foreign workers".
He said the Government would have to carry out a "360 degree shift" in policy before talks on a new national pay agreement could begin.
Head of Siptu's marine branch Paul Smith said the dispute was "the harbringer of a larger problem for the Irish economy."
"Seafarers from foreign countries are being asked to work on ferries worth €100m for 12 hours a day, seven days a week, for months on end, with no possibility of coming ashore, for €3.50 an hour. This is a bridge too far," he said.
Irish Ferries chief officer Noel Fagan said he was marching to obtain justice for Irish seafarers and to ensure that foreign workers were not exploited "in the name of greed" by Irish Ferries.
Matthew Finnerty (57), who has been a Marine Engineer with the company for 27 years, said that the company's actions were unethical and driven by the greed of a small number of people.
"I certainly won't be working again at my age. Myself and all my colleagues, from the galley boy up, have put a huge amount into this company and have built it up to make it the success it is," he said.
In a statement this afternoon, Irish Ferries said that while they understood the concerns expressed by the unions the case in question was unique and should be viewed as such.
The company said it was "struggling to compete with a domestic cost base which is wholly out of line with its international competitors in the shipping sector."
"Change is needed now to bring the company¹s cost base into line with its sea competitors, allow it to compete with low-cost airlines and ensure a future for the company," it said.
The Labour Court is due to hear the Irish Ferries dispute next Monday but the company has said it is going to go ahead with its redundancy plans regardless.