Treasurer Troy Buswell is staring down a Cabinet revolt as ministers in charge of big spending portfolios refuse to heed his call for voluntary spending cuts to protect the Budget surplus.
Mr Buswell had asked ministers to submit lists of programs no longer delivering value for money to his office by last Friday.
But Education Minister Peter Collier has not done so, Health Minister Kim Hames has found savings worth a pittance while calling for much more spending and Police Minister Liza Harvey said she fully expected new spending committed during the election to be delivered in full.
The West Australian also understands Agriculture Minister Ken Baston has identified no savings from his department.
Meanwhile, the Opposition has accused the Government of "cooking the books" after a change in Treasury iron ore price forecasting methodology sliced $1.5 billion in revenue from the forward estimates since the March State election.
Dr Hames, whose $7 billion health budget consumes about $1 in every $4 of Government spending, said he had identified $10 million of savings. "I'm not saying that I'm going to get $10 million less," he said.
"It means instead of getting $180 million more, I might get $170 million more."
Mr Collier said he was mindful of the State's financial constraints but he was yet to submit a list of programs in line with Mr Buswell's request.
Despite their reluctance to offer up cuts, Mr Buswell insisted ministers understood the scale of the financial challenge, which he claimed was greater than he faced after the GFC in 2008-09. But he issued a clear warning that budgets could be slashed if sufficient savings were not found.
"Ministers have an opportunity to participate in (corrective measures), but that's not by any means the limit of the net we will be casting," Mr Buswell said.
Shadow treasurer Ben Wyatt said the "politically convenient" $1.5 billion writedown of royalty revenue sparked by a methodology change was "economic spivery".