West Australian Premier Colin Barnett remains committed to leading the Liberal Party to the next election, despite a disastrous opinion poll and a state budget marred by record levels of debt and deficit.

The Premier's approval rating dropped in the latest Newspoll to just 32 per cent, well behind Labor's Mark McGowan on 46 per cent.

Importantly, Labor retained the 9 percentage point jump in its primary vote recorded at the December poll, holding steady at 42 per cent.

On top of his poll problems, Mr Barnett now faces the daunting prospect of convincing the electorate to give him a third term as his Government heads towards a $3.9 billion budget deficit.

Mr Barnett believes he remains the best person to lead the party to the election next March.

"If any member was dissatisfied with my leadership and thought they should be leader or could do a better job, they would come and talk to me about it. You know, they are all my friends," he said.

The Premier played down leadership chatter among some Liberals as a normal part of politics and said he was unaware of any concerns about it.

"No-one has raised the issue with me at all," he said.

"I've been a leader for a long time and I'm very open in my approach and I've always said I will do my best for the Government and the Liberal Party."

Treasurer not interested in being Premier

Treasurer Mike Nahan spent the day selling the budget, and when asked by reporters, ruled out any interest in pursuing the leader or deputy leader's position.

"We have a beautiful deputy. She just got appointed a month or so ago. And Colin is the leader," he said.

Opposition Leader Mark McGowan said it was clear the Liberal backbench was nervous about the electoral impact of the state budget.

"There's lots of speculation around and you can see it on the face of Liberal backbenchers that they're not happy with what the Government has done," he said.

But while Mr Barnett remained confident of his leadership position, he conceded the continuing poor polling was worrying Liberal MPs, particularly those in vulnerable seats.

"Of course people are concerned and I'm concerned. We're going to do all that we can to retain government. We recognise it's a tough task," he said.