Victoria's corruption watchdog has launched an investigation into allegations of "industrial-scale" branch stacking by Mr Somyurek, following an expose aired by Nine.

Mr Byrne was embroiled in the scandal after it was revealed covert recordings that exposed Mr Somyurek's operation, including the alleged forgery of party membership forms and verbal attacks on colleagues, were captured in his office.

Explosive texts written by Mr Byrne were released by Mr Somyurek on Wednesday night after his former ally agreed to cooperate with corruption investigators.

Mr Somyurek told reporters outside his home on Thursday he had learned the art of "branch work" from Mr Byrne.

"Anthony Byrne is someone I respect ... everything I know now about branch work, Anthony taught me," he said.

He described Mr Byrne as a "dear friend", but held concerns for his mental health.

"I'm not sure what went wrong. I am really worried," Mr Somyurek said.

Mr Byrne has been approached for comment.

He has been counselled by Opposition Leader Anthony Albanese over his "completely unacceptable and inappropriate" text messages.

It comes as Victorian Premier Daniel Andrews urged anyone approached by authorities investigating the affair to cooperate.

"Victoria Police, IBAC and the ombudsman, and any other bodies who seek to look into these very serious matters should be fully supported and should be fully cooperated with," he said.

"All Victorians, regardless of what office they hold, should fully cooperate with all investigations."

Mr Somyurek was sacked from state cabinet and quit the party after the expose, which aired on Sunday.

His right-faction allies and fellow ministers Marlene Kairouz and Robin Scott later resigned from cabinet, following allegations their staff were connected to Mr Somyurek's efforts.

Opposition treasury spokeswoman Louise Staley said the scandal showed the government was more focused on "factional crap" than creating jobs to help facilitate the state's recovery from the pandemic.

"They're not focused on getting Victorians back to work, and that's what businesses large and small are crying out for," she told reporters.

But Mr Andrews said he would not be sidetracked by the week's events, stressing repair of the state's economy was simply too important.

"We are going to keep pushing forward - jobs, that's the key at the moment," he said.

Mr Somyurek denies the branch stacking allegations, while Ms Kairouz and Mr Scott have vowed to clear their names.

The Independent Broad-based Anti-corruption Commission confirmed on Wednesday it had launched Operation Fortescue to investigate "serious allegations of corrupt conduct" within Victorian Labor.

Victoria Police and the Victorian ombudsman also been asked to investigate.

Former premier Steve Bracks and former federal minister Jenny Macklin have been appointed administrators of the Victorian party until January, to reform its structure and ensure its membership is legitimate.

Voting rights for rank-and-file members are being suspended until 2023, while every member is audited to ensure they genuinely want to be members and have paid the fees themselves.

Australian Associated Press