Unite the Union members working for Aker Solutions on Equinor's Mariner oil platform voted for strike action relating to pay, Britain's largest workers union said in a statement on Friday.
The strike would involve about 200 workers and would likely take place between early August and early October.
The Mariner field is located near Britain's Shetland Islands and is a major project that was due to start production in the second half of this year.
Reporting By Julia Payne; Editing by Kirsten Donovan
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