Opposition Leader Mark McGowan has called for the Commonwealth to share billions of dollars of future petroleum royalties 50-50 with the States on a per capita basis in a bid to partially address WA's seemingly intractable GST problem.
Mr McGowan says there should be a national debate over revenue collected under the Commonwealth's petroleum resources rent tax, which is likely to increase massively beyond the next decade as big offshore oil and gas projects off WA and the Northern Territory and in Bass Strait reach their full production stage.
Mr McGowan stressed Labor's position was that future gas projects should be developed onshore wherever possible.
He would continue to advocate for WA to get a fairer share of the GST.
But he said PRRT was set to deliver billions of dollars of new revenue that had not yet been allocated for spending.
So, the time was right to put the issue on the national agenda.
"Once all the write-offs and deductions for companies' capital investment are in place, a 40 per cent tax take on the profits of offshore oil and gas projects is a massive revenue boost, especially given some pretty major projects will come on stream over the next 10 years or so," he said.
"When revenues from some of these projects start flowing, in all likelihood Tony Abbott will no longer be prime minister, the current crop of Federal ministers won't be there and most of the State premiers and opposition leaders in all likelihood will no longer be there.
"So I think it is potentially easier for a national agreement to be reached (now) that would reinvigorate the Commonwealth and send revenue to the States, which undertake most of the service delivery, while still providing a massive revenue source for the Commonwealth."
Mr McGowan said there was a good chance that floating liquefied natural gas technology was likely to be preferred for a growing number of projects, robbing WA of local jobs, domestic gas supplies, payroll tax and rates revenue for local government.
"That's a pretty big loss to the State from this technological development," he said.