Premier Colin Barnett has defended plans for a state future fund after Opposition Leader Mark McGowan labelled it a "stunt" and said state debt should be paid off first.
Mr Barnett says Treasurer Christian Porter will outline the framework for the fund when it is set up in the next state budget in May.
The premier said it was a case of taking some of the prosperity WA was enjoying now and preserving it for future generations.
But Mr McGowan said the future fund was a "stunt" when state debt was more than $15 billion.
"You can't create a future fund before you pay off state debt because it's meaningless," he said.
Mr Barnett said WA was the world's leading mining economy and was going through an historic period of growth.
"The resource ultimately is finite, I think we've got 30 to 50 years of high-level mining activity.
"We should take a small part of that wealth on a yearly basis and preserve it for life after mining."
Mr Barnett said that was good long-term mining and he rejected Mr McGowan's assertion that WA could not have a future fund if it had debt.
He said former federal treasurer Peter Costello set up a future fund at a time when the commonwealth government had net debt.
"One is a big picture view, one is a small and miserly and selfish `this generation' view," Mr Barnett said.
He said the fund would most likely start in a modest way but accumulate over the next 30 years into billions of dollars.
