Treasurer Joe Hockey has rounded on Liberal Premier Colin Barnett in a partyroom stoush on the amount of GST revenue Western Australia receives.

And in a worrying sign for the Treasurer, who has been under pressure for his performance selling the budget, he was interjected upon by Liberal deputy leader Julie Bishop and rebuked by Prime Minister Tony Abbott.

Treasurer Joe Hockey's contribution to the debate in the party room was "extraordinary", according to one MP. Credit:Andrew Meares

Sources told Fairfax Media the showdown was sparked when former WA state treasurer turned federal MP Christian Porter stood up to argue for a greater GST share for Western Australia. He was delegated to speak for his WA colleagues.