A potentially damaging strike that could have shut down operations at Australia’s largest export port has been called off.

But the possibility of a future strike is still on the cards, with unions set to make another bid for industrial action after June 30.

Maritime Union of Australia (MUA) members employed by tugboat operator Teekay at Port Hedland in Western Australia voted last week to walk out if they were unable to agree to pay and conditions with the firm.

Imminent strike action was averted late Thursday when the union agreed to halt industrial action against Teekay for 30 days.

No settlement was reached over leave and wages but the union said it took industrial action off the table to allow negotiations to proceed.

However, it wants to reserve the right to strike after the 30-day cooling off period if no settlement has been reached.

On Friday, it will put in an application to the Fair Work Commission (FWC) to extend the period in which it can take protected industrial action by 30 days.

It will continue to hold informal talks with Teekay and will appear before the FWC on June 5.

The agreement between the union and the tug operator breaks an 11-month deadlock in talks over pay and leave entitlements.

The prospect of a strike had worried mining giants BHP Billiton and Fortescue Metals Group, both of which were at threat of losing sales.

BHP, which contracts Teekay, warned a strike would cost up to $700 million and flagged using legal action to prevent the strike.

Fortescue Metals had threatened to stand down workers if they went ahead with the strike.

The fractious situation also caused the federal government to weigh in.

Government officials were sent to Port Hedland to monitor the situation in a bid to protect Australia’s most valuable export industry.