The union’s shipping and docks conference in Hull today heard that Stena intended to break its national agreement by paying Polish crew aboard the Stena Seatrader at rates below those paid to UK ratings when the vessel begins operating between Holyhead and Dublin in July.

Delegates unanimously called on the RMT executive to begin an emergency campaign “at all levels” to defend the port agreement, including urgent approaches for assistance to sister unions through the International Transport Workers’ Federation.

“We have an agreement with Stena that sets out the rates that must be paid to ratings working out of Holyhead, and we expect them to stick to it,” RMT national secretary Steve Todd said.

“The Irish Sea has become the latest battleground in the struggle to stop shipowners replacing organised crews with low-cost labour, and Stena are now breaking their pledge that they will not join the ‘race to the bottom’ in seafarers’ pay.

“The introduction of low-cost crew to Holyhead is the thin end of a massive wedge which threatens to undermine the jobs, pay and conditions of ratings at Holyhead and beyond.

“The nationality the seafarers aboard the vessel is irrelevant, but they must be paid the rate for the job agreed between the company and the union.

“There is massive anger among the crews of the Explorer and Adventurer, the two Stena vessels already operating out of the port, and we have already had calls to start balloting for strike action.

“Stena should understand that we will take the necessary steps to defend our national agreement, and that RMT will back industrial action by our members if it becomes necessary,” Steve Todd said.