Western Australia’s largest container port – as well as major bulk cargo jetties critical to the import of fuels and fertilisers – could grind to a halt next week as a small group of key Fremantle Ports workers threaten to walk off the job amid a pay dispute.

About 40 pilot boat operators and vessel traffic service officers have threatened to take industrial action, which could include day-long stoppages, unless Fremantle Ports significantly improves their pay.