Industrial action at Belco could leave customers in the dark, the utility warned over the weekend.

The company said customers “may experience power outages” as a result of the industrial action with the Electrical Supply Trade Union, which imposed a work-to-rule after the departure of four of the management team.

The action impacts overtime and emergency work at the energy provider. The ESTU has called for the reinstatement of the staff.

The company said there were always staff to monitor the plant and, if necessary, perform emergency shutdowns, but it would not have adequate resources to respond to issues on the network and customers might experience “prolonged outages”.