Western Australia's Labor government is facing further industrial headaches with nurses planning to strike over pay and conditions.
About 84 per cent of the 4800 members who responded to a union poll have rejected the state government's latest pay offer.
A state-wide strike has been organised for Friday, with nurses encouraged to rally outside parliament.
The decision came just hours after Premier Mark McGowan revealed several of Australia's biggest miners would chip in a combined $750 million to a new community investment fund.
Rio Tinto and BHP have each committed $250 million, with other contributions from Hancock Prospecting, Woodside Energy, Chevron and Mineral Resources.
WA's most recent budget surplus swelled to $6 billion on the back of mining royalty revenue.
The nurses union had initially backed the government's latest pay offer and agreed to call off industrial action, only to reverse its position after a backlash from members.
Any potential strike could leave the nurses union facing a hefty penalty from the state's industrial umpire, which had ordered a deferral of the ballot.
The state government is offering nurses and midwives a three per cent annual pay rise and a one-off $3000 bonus.
It has also agreed to implement nurse-to-patient ratios and allow employees to more easily cash out leave.
Police have also ramped up their pay dispute with the McGowan government, threatening to issue cautions rather than fines for minor traffic offences.
Their union has also flagged the prospect of officers parking their vehicles in front of speed cameras.
Mr McGowan has urged nurses and police officers to follow other public sector workers in accepting what he has described as a generous pay offer.
The premier is hopeful of securing commitments from other mining companies to grow the resources community fund to more than $1 billion.
He said it would help to bankroll projects including the new Aboriginal Cultural Centre and redevelopments of Perth Zoo and the Perth Concert Hall.
"It's just a good way of getting some additional support for important projects around Western Australia, reducing the burden on the taxpayer," he said.