Workers at the Faslane nuclear base are to go on strike and take other forms of industrial action after rejecting a "derisory" pay offer.
Unite suspended a planned stoppage last month at the site on the Clyde in Scotland, but has revived action after most of its members turned down a 2% offer.
A two hour walkout will be held from 10am on March 11, followed by "staged stoppages" as well as a work to rule and overtime ban.
The dispute is between Unite and contractors Babcock, which the union claimed was paying "eye watering" bonuses to top directors.
National officer Ian Waddell said: "Babcock's top four directors are making hay, sharing £7 million between them and then taking a 9% increase on their basic pay. All the while the company sees fit to impose years of real-term cuts on a workforce that has done everything to help this private sector giant fulfil its business objectives.
"It's now a case of the chickens coming home to roost for Babcock Marine on the Clyde which has been well warned about the ramifications of its grossly unfair pay policies. Our members are no longer prepared to play the part of the poor relations.
"We entered talks, suspending our industrial action in good faith, in the hope that we could negotiate a deal that would give this loyal workforce the fairness it deserves, but the company tabled its new position and that was the end of the matter.
"A prolonged period of industrial action will severely disrupt day-to-day operations at the Faslane and Coulport bases, but the workers will strive to ensure the safety of the workforce, the naval base and the local communities will not be compromised.
"Unite remains ready and willing to sit down with Babcock again or indeed under the auspices of the conciliation service to try and resolve this dispute which can be easily avoided but the ball is firmly back in the company's court."