Nats, Liberals in WA preference war

A state election preferences war in Western Australia between the Liberals and Nationals was inevitable, says federal Nationals leader Barnaby Joyce.

The WA Nationals on Tuesday confirmed they would preference the Greens ahead of the Liberals in two state upper house regions, impacting on the prospects of a Barnett government minister.

The move came after the Liberal Party secured a deal to preference Pauline Hanson's One Nation ahead of the Nationals, which is in a coalition with the Liberals federally but not in WA.

Mr Joyce said the Nationals-Greens deal was not a good idea.

"It's all retaliation," Mr Joyce told Sky News.

"This is what happens when you start picking on your business partner or your girlfriend - one person scratches and the other scratches back. I don't think they are outcomes you want."

Mr Joyce said voters had a right to question the Liberals' deal with One Nation.

"If I'm in business with you then I never expect a third party to come in, otherwise the natural thing is to say: 'You are in a coalition with them, are you?'"

Labor leader Bill Shorten told a caucus meeting in Canberra on Tuesday the deal had federal implications.

"One Nation is fast becoming a faction of the Liberal party," Mr Shorten said.

Social Services Minister Christian Porter, who hails from WA, said the Liberals and Nationals in WA operate in a "very idiosyncratic and different and unusual" set of circumstances.

Mr Porter said the Nationals had made similar deals several elections ago.

"The Nationals ... act completely independently of the two major parties in the way it negotiates for government," he told ABC radio.

The Queensland Liberal-National Party is considering a deal with One Nation after a Galaxy poll showed the minor party sitting on 18 per cent of the primary vote.

With a strong flow of One Nation preferences the LNP could unseat the Labor state government, or go into minority government with Senator Hanson's party.

Attorney-General George Brandis, who represents Queensland in the Senate, said Senator Hanson was an "extremely pleasant person".

"She's very polite. All she wants, as everyone is entitled to, is to be treated with professional courtesy but that's what the Labor Party refuses to do," Senator Brandis told 2GB radio.

Asked whether he agreed One Nation had become more "sophisticated", as federal minister Arthur Sinodinos said on the weekend, Mr Joyce said its "delivery is more polished" than two decades ago.

He declined to say whether he would preference One Nation last at the next federal election, adding he would need to read the party's policies and see if there were other parties more worthy of being put last.

Nationals MP Andrew Broad said his Liberal colleagues needed to show more faith in the coalition, which had been the most successful political pairing in post-war Australia.

"It's a model that works. Believe in it," Mr Broad said.