The RMT trade union said port workers will go on strike in Aberdeen later this week in a dispute over “pay justice”.
Engineering and servicing staff will also refuse to work for 48 hours in Newcastle and Portsmouth.
RMT General Secretary Mick Cash said: “This dispute is about a key group of port-based staff fighting for a fair pay deal that protects and enhances their standard of living and sends out a key message that this trade union will not accept austerity and attrition in the shipping and offshore industry.
“The company are well aware of the feeling on the ground- reflected in massive votes for action – and they should start respecting the views of the workers delivering these highly-skilled services.
“RMT remains available for talks.”