Dublin's Port Tunnel could close if a planned strike action by Siptu goes ahead in two weeks time.
Siptu branch organiser Owen Reidy said the union had served 14 days strike notice on Transroute Tunnel Operations, the operator at the tunnel, over a pay dispute with the company.
Siptu members voted unanimously in favour of industrial action after they rejected a Labour Court recommendation, which they claimed left a large number of workers worse off than at present. The strike is due to go ahead on July 23rd.
In a statement issued this afternoon, Transroute said it was still in negotiations with Siptu in relation to the pay dispute and anticipated the matter being resolved in a satisfactory matter.
Mr Reidy said that because Transroute does not give the normal shift pay, Sunday or overtime rates that are common in the industry, some members could expect to earn 30 per cent less than the average industrial wage.
Transroute had taken the dispute to the Labour Court but Siptu revealed it was not prepared to abide by their recommendations.
Mr Reidy said the Labour Court intervention left a large number of workers worse off than before.
He said after a year of campaigning unsuccessfully for improved pay, workers were left with no alternative. "Their frustration can be seen when the vote for industrial action was 100 per cent in favour", he added.
Transroute runs the operation and maintenance of the tunnel including the toll booths, traffic management, safety, emergency and contingency plans and inspections.