Workers at BP’s refinery in Rotterdam have, as of Monday, started a ”work-to-rule” action after negotiators weren’t able to reach a salary settlement, reports Reuters.

”Work-to-rule” means staff are refusing to carry out tasks beyond those specified in employment contracts.

This action comes as a response to BP’s failure to respect the agreement deadline set by the workers’ labor union, the news agency writes.

According to a spokesperson from CNV, a federation of Dutch trade unions, the action will be followed by workers decreasing refined fuel volumes, potentially also leading to a full-blown strike if a satisfactory settlement is not landed.

Discussions and negotiations on a new collective bargaining agreement have been underway since April, and while BP has offered a 5% pay raise, workers are demanding 6%, citing factors such as high inflation.

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