NSW MP John Sidoti looks likely to be forced out of parliament after he was found by the state's anti-corruption body to have engaged in serious corrupt conduct.
Premier Dominic Perrottet was asked about his former Liberal cabinet colleague on Thursday, after he landed in Tokyo for a 10-day trade mission.
Mr Perrottet says he has sought legal action about moving a motion to have Mr Sidoti suspended from parliament, after the Drummoyne MP refused to call time on his political career.
"The only appropriate thing is that any member of parliament who has such findings (corrupt conduct) against them should resign," he told reporters.
"There could be nothing more important than upholding confidence in our democratic institutions."
The Independent Commission Against Corruption found against the former Liberal minister on Wednesday and recommended the Director of Public Prosecutions be consulted about possible criminal charges.
The anti-corruption watchdog investigated the now independent MP over his lobbying of local councillors to rezone blocks at Five Dock in Sydney, where his family owned property.
Mr Perrottet phoned Mr Sidoti on Wednesday night, giving him an ultimatum to resign from parliament - or face an expulsion motion.
Mr Sidoti said his response was brief.
"It was two words and I can't mention them on camera," he told Sydney radio 2GB on Thursday.
Treasurer Matt Kean is also urging the former sports minister to resign.
"I'm offended by what I've read about Mr Sidoti's behaviour," he told reporters on Thursday.
Mr Sidoti insists he will not resign, saying he will "absolutely" prove his innocence. He has instructed his lawyers to lodge an application in the Supreme Court.
"The reality is I'm innocent, I'm going to fight this ... on principle," he said.
He criticised the ICAC, saying it was "a ridiculous system" that needed reform, adding he had endured "three years of misery" as the inquiry dragged on.
"There have been many innocent people before me who have gone through what I've gone through, their reputation is tarnished, their life is trashed," he said.
The ICAC found Mr Sidoti misused his position as an MP to pressure and threaten City of Canada Bay Liberal councillors to rezone land to benefit his family's property interests.
Mr Sidoti said his business interests in Five Dock, where his family owned a function centre, were well known by everyone in the area.
"So the idea that somehow they didn't know or they lost their memory is just unacceptable," he said.
Australian Associated Press
