Morrison contradicts Barnett over GST

Treasurer Scott Morrison has rejected the West Australian premier's suggestion he could intervene to change the GST carve-up.

Colin Barnett last month said it was wrong to say the GST distribution was a matter for the states to unanimously agree on because it was an issue for the Commonwealth Grants Commission "and the only politician in this country who has any authority over it is the federal treasurer".

"That's not our understanding - it does require working with the states and territories to work through this issue consultatively," Mr Morrison told reporters in Perth on Wednesday.