Showdown for NSW Liberal leadership looms

After behind-the-scenes factional wrangling for much of the weekend, Mr Perrottet on Sunday confirmed he would seek to become the next premier.

Long touted as the 'heir apparent' to Gladys Berejiklian, the treasurer has appealed to his Liberal colleagues after striking a deal to make Jobs Minister Stuart Ayres his deputy and promote Environment Minister Matt Kean to treasurer.

He is a member of the Liberal Party's right faction, while Mr Ayres and Mr Kean are from the dominant moderate faction.

But Mr Stokes, also a moderate, is refusing to follow his factional colleagues, on Monday confirming he would not withdraw his nomination to be party leader.

The Pittwater MP has offered himself as a more experienced alternative to 39-year-old Mr Perrottet, arguing he was the party's best shot at winning the 2023 election.

"Dominic Perrottet is a good friend of mine. He has a lot of great qualities. I just believe in terms of experience that I offer more," he told reporters on Monday.

But the 47-year-old remained coy on his chances of winning the leadership when the Liberal party room meets on Tuesday to vote for their new leader.

"That is up to my colleagues," he said.

"I feel very confident that I have every chance of being successful but, after all, the main game here is to give a choice to the people of the party room."

Both candidates are fitness fanatics, fathers and men of faith.

But while Mr Stokes was elected to parliament as in 2007 during the Labor Iemma government's tenure, Mr Perrottet - elected in 2011 - has not spent any time in opposition.

Mr Perrottet has bounced around three electorates in as many terms - Castle Hill, Hawkesbury and Epping.

Both have served as ministers in several portfolios since 2014. Mr Stokes was minister for environment and education, while Mr Perrottet took on the finance and industrial relations portfolios before becoming treasurer.

Mr Perrottet on Monday played up his credentials working alongside Ms Berejiklian as deputy leader, and argued for stability.

"As Gladys demonstrated so well, leading a successful Liberal and National government requires unity across our party's 'broad church'," he wrote in an opinion piece published in The Daily Telegraph on Monday.

"We can only do that if we remain united, and maintain stability and continuity for the people of our state."

Former prime minister and Liberal party elder John Howard has backed Mr Perrottet, saying he is driven and reform-focused.

Ms Berejiklian quit on Friday after the state's corruption watchdog disclosed she was under investigation for potential breaches of public trust given her secret five-year relationship with former MP Daryl Maguire.

She will formally step down as leader when the party elects her replacement, and will quit parliament altogether when a by-election for her seat can be arranged.

It comes as the NSW Nationals prepare for their own leadership contest.

Deputy Premier John Barilaro on Monday announced he too would leave state parliament, saying it was time for a "refresh" as much of the state prepares to emerge from nearly four months of COVID-19 lockdown.

Nationals MPs Melinda Pavey, Paul Toole and Adam Marshall are believed to be the main contenders to lead the junior coalition party and become the new deputy premier.

Mr Barilaro's resignation means the NSW government faces three by-elections in coming months for the seats of Willoughby, Bega and Monaro, after Transport Minister Andrew Constance on Sunday also announced he was leaving to attempt a switch to federal politics.

Opposition leader Chris Minns on Monday blasted Mr Constance and Mr Barilaro for resigning during the pandemic.

"That you've got a new job opportunity or you'd like to move into a new political arena is not a good enough reason to abandon your electorate and start a new career, particularly during a pandemic," he said.

By-elections cost upwards of $1.5 million each, he said, and urged them to reconsider their decisions to quit.

Australian Associated Press