Siptu has disputed claims by the Taoiseach that the Government could do "no more" to prevent Irish Ferries from going ahead with its controversial redundancy plan.
Siptu president Jack O'Connor said today there were still avenues open to the Government if it chooses to use them.
Jack O'Connor, Siptu
Yesterday Mr Ahern said he feared the dispute was not going to be resolved, given the company's refusal to accept Labour Court recommendations on the issue. He said the Government had looked at several options to resolve the matter - including withholding statutory redundancy payments - but none proved viable.
Siptu is in dispute with Irish Ferries over its plan to lay off up to 543 unionised seafarers and replace them with cheaper agency staff from eastern Europe.
But Mr O'Connor said he believed Mr Ahern was acting in good faith upon advice but argued the Government was responsible for health and safety issues, including the care of people working within the territorial waters and using Irish ports.
"The implications of what Irish Ferries are pursuing are directly at variance with the health and safety of the people they would be employing and by implication indirectly the people who would be utilising the service," he said.
"One of the elements of the cheap labour policy that they are committed to will have implications for health and safety, in that people will be ensconced on those boats for very long periods at a time without breaks and so on," he said.
Irish Ferries has consistently maintained that its domestic cost base is out of line with its international competitors and that it must implement the plan to stay in business.
Last night ships' officers at the company balloted to take industrial action in the event of the company implementing its plan. The union is obliged to serve two weeks' notice of any action on the company.
But Mr O'Connor said: "I am making it very clear there would be absolutely no industrial action or no strike if the company continues to comply with the existing agreement".