Clive Palmer's near-$30 billion damages claim against the West Australian government would force the mass closures of hospitals and schools, the premier has claimed while defending an extraordinary bid to block the suit.
Mr Palmer's Mineralogy company is pursuing WA for damages over a 2012 decision by the then-Liberal government to refuse to formally assess its proposed Balmoral South iron ore mine in the Pilbara.
Late on Tuesday, WA Attorney-General John Quigley told state parliament Mr Palmer and his associated companies Mineralogy and International Minerals were claiming a total of $27.7 billion minus costs - a figure Mr Palmer disputes.
Premier Mark McGowan has labelled the move "obscene" and is urging the state opposition and crossbenchers to support unprecedented legislation to block the claim.
"He is trying to take our money and if he's successful that would mean mass closures of hospitals, of schools, of police stations, mass sackings ... it is an extreme risk to Western Australia," Mr McGowan told reporters on Wednesday.
"I will not risk selling Western Australia down the drain to Clive Palmer."
Mr Palmer claimed he and the WA government had previously agreed to mediate the dispute, adding the proposed legislation, which would terminate the arbitration between the two parties, would damage the state's reputation.
"The attorney-general really says that he thinks 'we're guilty and we're going to have to pay up'," he told Perth radio 6PR.
"I think it would be very bad to do. Western Australia's been a very successful state based on the sanctity of its state agreement and its sovereign risk.
"If it passes this act, all that's out the window. Its credit rating's liable to go down and people that have invested in this state will be worried about what's going to happen."
Mr Palmer said the damages were yet to be assessed, labelling talk of a $30 billion claim "bulls***".
But the attorney-general has dared Mr Palmer to waive his confidentiality under the Commercial Arbitration Act to "put it all out on the table".
Mr McGowan said he had spoken to mining industry stakeholders and assured them his emergency legislation did not create sovereign risk or threaten other state agreements.
"We have around 70 state agreement acts in Western Australia. They have been around now for 70 or 80 years," he said.
"This has never happened before. Ministerial decisions have always been accepted and worked through between the state government and proponent."
Mr McGowan denied the dispute was linked to Mr Palmer's ongoing legal bid to have WA's hard border closures deemed unconstitutional. He hopes to have the bill passed by Thursday, warning that every day is costing taxpayers.
The state opposition was only briefed on the legislation on Tuesday night.
"My conscience is clear. I know we are doing the right thing by the state," Mr McGowan said.
"I wasn't elected to cave into these sorts of personal interests."
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