Prime Minister Malcolm Turnbull has accused the media of living in a "parallel universe" in response to suggestions West Australians are angry at him and his Government over the state's low GST share.

Mr Turnbull made the comment before departing Perth after a lengthy visit dominated by questions about WA's GST share and his Government's response to it.

Mr Turnbull has also repeatedly faced questions about the Liberals' poor polling in WA, which many within the party link to the GST.

The WA Government was already angry about its GST share, which is much lower on a per capita basis than any other state, before finding out revised population estimates could cost it another $2 billion in lost GST revenue over four years.

But the Prime Minister rejected suggestions people were "angry or furious" at him over the issue, saying his experience from his time in WA did not convey that message.

"I have met with hundreds of West Australians this week ... and the reception I have had could not have been warmer, more positive or more welcoming," Mr Turnbull told ABC Perth.

"It is a complete parallel universe between what the media is saying and what the people I am meeting in the real world is what people are saying to me."

GST 'unfair': Turnbull

Mr Turnbull did concede there was community "concern" about the GST situation, again describing WA's return as "unfair".

His visit to Perth also saw him become embroiled in a public slanging match with WA Premier Mark McGowan over the GST yesterday.

Prime Minister accused the Premier of being "belligerent" after Mr McGowan said Mr Turnbull should "stop acting like Tony Abbott" and said WA would have been better off if he had stayed home and given the money to the airfares to the state.

But the two leaders turned these snipes into smiles as they opened a freeway extension together in Perth's north this morning, both brushing away suggestions of a feud between the pair.

Mr Turnbull and Mr McGowan were all smiles as they opened the Mitchell Freeway extension. ( ABC News: Jacob Kagi )

"I am not going to abuse the Prime Minister at the opening of a freeway, it would be unreasonable to suggest I was going to do that," Mr McGowan said.

"Yesterday was a tense day, last night we had a meeting and talked about lots of issues but I suppose you've got to keep on talking."

Mr Turnbull said his 90-minute meeting with Mr McGowan last night was "friendly, cordial and constructive", a sentiment echoed by the Premier.

The Prime Minister arrives in Broome this afternoon and will spend the night there, marking the end of his week-long WA visit.

He is tentatively scheduled to return to WA early next month, for the Liberal Party's state conference.