Industri Energi, Norway’s largest union of oil workers, said on June 6 it could potentially take up to 937 members on strike if the state-sponsored mediation due on June 27 fails to produce a deal with oil companies.

Most of the floating installations that could be affected by the strike are operated by Norway’s oil and gas firm Equinor, the union said in a statement.

A few installations are also operated by Aker BP, Vaar Energi, an independent subsidiary of Eni, and Shell, the union added.

The union yet has to notify the mediator’s office how many workers would go on strike initially.