Abbott not undermining Liberals: Barnett

Ousted prime minister Tony Abbott's commentary on the federal Liberal Party does not undermine Malcolm Turnbull's leadership, West Australian Premier Colin Barnett says.

Mr Abbott said his government was not given enough credit for its policies, none of which had changed since he was toppled by Mr Turnbull.

The premier denied Mr Abbott was undermining the new leadership, saying people outside politics could not understand what a "traumatic experience" he was going through.

"When you lose your job as prime minister it is a national and international humiliation, and I think we just (need to) cut Tony Abbott a bit of slack at the moment," Mr Barnett told reporters on Sunday.

"He's a good man, he's lost his job, I feel very sorry for him.

"At the same time, I think Malcolm Turnbull will prove to be a long-serving and very successful Australian prime minister."