Federal Minister Slams 'Unbalanced' GST Report as Labor Backs Western Australia

Federal Resources Minister Madeleine King has slammed as "unbalanced, highly speculative and clearly incorrect" an interim report that recommended a cut to Western Australia's share of the GST, reassuring voters that the Labor government was committed to supporting the resource-rich state.

Minister King was speaking a day after state Premier Roger Cook called the Productivity Commission report on GST distribution an "attack on Western Australians", and dubbed its authors "east-coast clowns".

"I want to make it clear to all Western Australians that the Albanese Labor government has your back," she said today as Labor officially launched its campaign for the hotly contested suburban seat of Secret Harbour, south of Perth.

The explosive report, which was released on Friday, recommended the government scrap 2018 changes to how the goods and services tax was carved up among the states, saying Western Australia was the only state or territory to benefit from it and that it was a "costly mistake".

Prime Minister Anthony Albanese, whose government has endorsed and extended the deal to at least 2029, has said that WA would "get [its] fair share" of GST but signalled he would wait for the final report in December to comment on specifics.

Cook says he has PM's assurances

Minister King said Mr Albanese had assured Mr Cook that there would be no change to the current arrangements.

"The report itself is not only unbalanced, it is highly speculative and is clearly incorrect. It fails to take account of the enormous contribution Western Australia and Western Australia's resources industry provides to the whole of the nation," she said.

At the same Secret Harbour event, Mr Cook also said he had the prime minister's assurances that the GST deal would remain.

"He knows that Western Australia is the engine room of the national economy," Mr Cook said.

The deal struck by then-treasurer Scott Morrison ensures WA gets a bigger slice of GST revenue every year than it would under the national formula, which is meant to give more money per person to states with the highest need and lowest financial means.

The formula has always been contentious, but became particularly so in WA when successive mining booms made it by far the richest state in the federation, resulting in very low GST relativities because the formula assessed the state as very high means.

Mr Cook's government, however, has maintained that changing the GST distribution would unfairly punish WA for its success, with state Treasurer Rita Saffioti saying that unravelling the deal would unfairly disadvantage the state.