Headed by former Federal Court judge Raymond Finkelstein, the royal commission will explore Crown's suitability to hold a casino licence within the state and the fitness of its associates.

It follows the release of a scathing NSW report on February 9 that found the casino giant facilitated money laundering through subsidiaries' bank accounts and failed to act when it was drawn to their attention.

Harold Mitchell became the latest in a long list of company directors to resign on Monday, following CEO Ken Barton, Andrew Demetriou, Guy Jalland and Michael Johnston out the door.

Victorian Gaming Minister Melissa Horne said the state government had gone through the 800-page Bergin report line by line and decided a royal commission was needed.

"The findings in there were so severe that the most appropriate action to protect Victorian interests was the establishment of a royal commission," she said, adding the move was backed by Premier Daniel Andrews.

She defended the delay between Commissioner Patricia Bergin handing down her report and the Victorian government establishing a major inquiry of its own.

"We needed that complex legal advice," Ms Horne said.

"We needed to understand what the commercial restraints are as well. We have done that work and the advice is the strongest possible response."

Federal MP Andrew Wilkie said a royal commission was "long overdue", while Victorian Greens leader Samantha Ratnam accused the state government of running a "protection racket for Crown".

Victorian opposition spokeswoman Steph Ryan labelled it "the royal commission Daniel Andrews didn't want to have".

It will supersede the Victorian Gaming and Liquor Regulation Commission's review into the casino giant, which was brought forward in December by two years.

Ms Horne swatted away questions over why it had taken an inquiry into Crown's proposed Sydney casino at Barangaroo to bring to light allegations of money laundering in their own backyard.

"Money laundering is by and large the remit of the federal government agency AUSTRAC," she said.

"The VCGLR had referred a number of things to AUSTRAC and really that is the jurisdiction of that federal government agency."

A review into the establishment of an independent casino regulator will also run parallel to the royal commission.

Commissioner and chair Mr Finkelstein QC, who served as a Federal Court judge from 1997 to 2011, is expected to report back with recommendations on August 1.

"This is going to be a fast-tracked royal commission," Ms Horne said.

"We'll see what those findings are ... and then stand ready to act."

The state government has committed to giving the regulator any new powers it requires to enact findings.

It is estimated the royal commission will cost Victorian taxpayers in the ballpark of $5 to $7 million.

Crown has pledged to fully co-operate and continue to engage with the VCGLR and government on its reform agenda "to deliver the highest standards of governance and compliance".

"Victorians should be assured we recognise the responsibility placed on us by the community, governments and regulators," executive chair Helen Coonan said in a statement.

Australian Associated Press