The West Australian Premier has threatened to withhold campaign funding from the federal Liberal Party if it does not commit to reforming the Goods and Services Tax.
He has taken a fresh swipe at the Federal Government's handling of the issue and also sent a message to the Opposition Leader, Tony Abbott.
"That will be a critical issue in the federal campaign," he said.
"Last federal election there was massive funding from Western Australia towards the national Liberal campaign.
"That will be reliant on a commitment on GST."
Mr Barnett says the financial support is at risk.
"I'm just making an observation," he said.
"The support that the federal Liberal Party got from Western Australia will depend on the GST issue.
"Not only support from within the Liberal Party but support from the corporate sector."
He says Mr Barnett is a powerful advocate for Western Australia.
But, Mr Abbott will not say what he would plan to do with the GST.
"He is stating a case, a case which has had some support from the other Liberal Premiers and I'm looking forward to the response from the Greiner-Brumby report," he said.
"My response you'll get in good time before the next election and after the Government's response."
The WA Opposition Leader, Mark McGowan, has scoffed at the Premier's threat to withhold campaign funds.
Mr McGowan has told Fairfax Radio, Mr Barnett was one of the architects of the original GST deal and his threat is an election stunt.
"This is just something he's saying before an election to throw people off the scent of the fact that he is responsible for the situation we're now in and after the election it will all be forgotten."