The world’s largest bulk iron ore export operation could grind to a halt when workers walk off the job for an eight-hour strike over pay.

More than half of the 450 workers at BHP’s Port Hedland bulk export terminal in Western Australia are expected to strike for eight hours on Thursday.

It’s the first major industrial action to hit the resource-rich Pilbara region in decades, with estimates it could cost the state government $6.8 million in lost royalty revenue.

The mining giant and combined ports unions failed to reach a wage agreement following a five-hour bargaining session earlier in the week.

“It is the intention of workers and their representatives to proceed with protected industrial action notified for Thursday,” a spokesman said after the talks.

BHP said plans were in place to continue operations.

The Electrical Trades Union, the Western Mine Workers’ Alliance (Australian Workers Union), and the Australian Manufacturing Workers’ Union are involved in the industrial action.

They have called for an eight-hour work stoppage, with the action expected ​to run from 2pm to 10pm local time, stating BHP had failed to progress wage bargaining talks for more than six months.

BHP has expressed disappointment that the unions had decided to proceed with the strike following progress made during negotiations on Tuesday.

The miner said there had been eight bargaining sessions and it had offered a 16 per cent pay increase over four years for most workers, with improved allowances.

Union claims that there had been no progress in bargaining were inaccurate, it said earlier in the week.

“We remain committed to bargaining in good faith and believe involving the (Fair Workplace Commission) is the most constructive, transparent and fair way to achieve the best outcome,” a spokesman said.

Bargaining for BHP’s port operations agreement started in October 2025.

About 577 metric tonnes were exported from Port Hedland in 2024-25, worth an estimated $115.8 billion.

The company said it paid $2.8 billion in state royalties and related government payments in the 2025 financial year, contributing about nine per cent of all WA government revenue.

—AAP