Barnett, who has publicly opposed a plan spearheaded by WA Nationals leader Brendon Grylls to impose a $A5 per tonne tax on the two majors, reportedly said yesterday that he was not looking to impose higher fees on the two, but rather negotiate the timing of payments.

The ABC reported that the Premier wanted to scrap the current 25c/t levy and replace it with an upfront payment.

“That is an option but again can I stress nothing has been agreed but we are looking at that 25c fee because it is an anomaly," Barnett was quoted as saying.

"We are looking at that and discussing it with the companies but that hasn't progressed very far."

A spokesman for Rio Tinto said the company had been approached by the WA government to pay out its lease rental but was not planning to take up the offer.

“Rio Tinto is already making a significant contribution to the WA government,” he said.

“Since 2006 the company has paid $13 billion in royalties to the WA government – the equivalent of 10 new children’s hospitals.”

BHP was similarly unenthused.

“We can confirm the Premier’s statement that the WA government has discussed this idea with us,” a BHP spokesperson said.

“We can also confirm that BHP Billiton has not agreed to it and has no plans to do so.”

It comes as the Nationals launched pre-election advertising this week to spruik its $5/t tax plan.

The Chamber of Minerals and Energy WA said it was an opportunity for the party to “come clean” on its “job-killing” tax.

“At a time when the state is fighting for market share against other global iron ore producers like Brazil, Western Australia cannot afford a new mining tax,” CME CEO Reg Howard-Smith said.
 
“Under the anti-mining plan by the WA Nationals, Western Australia will become the highest taxed iron ore mining jurisdiction in the world, potentially costing billions in investment and thousands of local jobs, particularly in regional areas.”

According to the CME, the majors pay around $17/t in royalties and taxes to the state and federal governments.