Former WA police minister Rob Johnson has confirmed he will run as an independent in the upcoming state election, continuing a bitter battle against the Liberal Party.

Key points: Rob Johnson quit the Liberal Party in April after a long-running feud with the Premier

Rob Johnson quit the Liberal Party in April after a long-running feud with the Premier The former police minister was dumped from the ministry in 2012

The former police minister was dumped from the ministry in 2012 He has criticised the Liberal Party's preselection process for his seat, claiming another contender was discriminated against because he was Jewish

Mr Johnson quit the Liberal Party in April, saying he was not prepared to be "one of the crew on Colin Barnett's Titanic".

Mr Barnett dumped Mr Johnson from his ministry in 2012 and relations between the two have dramatically soured since then.

It had been widely expected the outspoken MP would contest the formerly blue ribbon Liberal seat of Hillarys as an independent.

Outside Parliament today, Mr Johnson said the Premier had broken too many promises.

"You know yourself the problem with Colin Barnett and the Liberal Government at the moment? He has been reckless, not only with the finances but reckless with the truth," he said.

"People are sick to death of him making promises at election time that he knows he will not keep."

Mr Johnson said a survey of more than 1,000 Hillarys voters showed 76 per cent wanted him to run again.

"Countless people have approached me since I became an independent Liberal and have encouraged me to contest the next election, and the survey's results have validated this support," he said in a statement.

Mr Johnson said he would fund his own campaign, and would not rule out supporting Labor in the event of a hung Parliament, saying he would be guided by the preferences of Hillarys voters.

"I would work with any government if they could do a good job. I would hold them to account. I promise you that, whether it is Labor, Liberal or a Coalition. I would certainly hold them to account, so I wouldn't rule that out but I wouldn't rule it in." he said.

Johnson critical of Kastsambanis preselection

The Liberal Party has preselected Upper House MP Peter Katsambanis as its candidate for Hillarys in the March election.

Mr Johnson has been highly critical of the Liberal Party's pre-selection process in Hillarys and the Liberal candidate, Peter Katsambanis.

Mr Johnson's supporter, Simon Ehrenfeld, comfortably won branch backing in a preselection vote, but the State Council intervened and selected Peter Katsambanis instead.

Mr Johnson initially claimed Mr Ehrenfeld was discriminated against because he was Jewish.

"The community do not understand why the powerbrokers have put in a candidate who only arrived in WA in 2010, nor do they like the dirty tricks that were played in his selection," he said.

"The local Liberals didn't want him and neither will the voters in Hillarys."

Mr Katsambanis said he was concentrating on local issues, despite what he describes as "personal attacks" on him by Mr Johnson.

"The decision to run is for other people to make. I am the endorsed Liberal candidate for the seat of Hillarys. As a local, who lives in Hillarys, my entire focus is on campaigning to make Hillarys a better place for all the families that live there," he said.

Mr Katsambanis said he was being targeted in personal attacks by the Member for Hillarys and his supporters.

"What I am concerned about are the continuing personal attacks, threats and intimidation from Mr Johnson and his cronies that I have been subjected to, and my family has been subjected to," he said.

"I call on Mr Johnson to stop what is clearly not a fair fight."

Mr Johnson denies he is behind any personal campaign against his Liberal opponent.

"Absolute rubbish. That's a typical thing for that person to say. I'm not even going to mention his name. He's not worthy of it," he said.

"He's done nothing in the electorate. He's been foisted on the people of Hillarys and the Liberal supporters there by the powerbrokers."

Senior Liberal MP Joe Francis said it was entirely up to Mr Johnson if he wanted to run as an independent.

"It's his right, he's a member of Parliament, he's a member of a free society, if he wants to run as an independent, he can run as an independent. Good luck to him," he said.

Mr Johnson won Hillarys at the 2013 election with 64 per cent of the primary vote.