However, some expressed concern that Mr Guy's decision to stay at the table after learning Mr Madafferi was there showed a lapse of judgment.

And some believed any further revelations could prove highly damaging for Mr Guy's leadership.

Mr Guy has repeatedly denied wrongdoing or discussing donations at the April meeting with, among other diners, Mr Madafferi and Mr Madafferi's cousin, long-time Liberal supporter Frank Lamattina, at the Lobster Cave restaurant in Beaumaris.

One senior Liberal MP said the party room was united behind their leader and so far there had not been any push for a leadership change.

"I don't get the sense that anyone genuinely wants change. It's a cohesive parliamentary party room," the MP said.

The MP said switching leaders was an "enormous risk", particularly with an election less than 18 months away.

"The party has to go through devastating convulsions to go there."

Mr Madafferi has never been charged with a criminal offence and denies any wrongdoing.

This week Fairfax Media revealed explosive secretly recorded phone calls in which a Liberal Party official discussed plans to offer undisclosed donations from the men who attended the dinner.

The official recorded in the phone calls, Barrie Macmillan, resigned from his party position on Wednesday.

The latest turmoil in Victorian politics is also facing scrutiny from Canberra.

Prime Minister Malcolm Turnbull, asked in Federal Parliament whether the Australian Federal Police had been asked to investigate the revelations, said, "Those reports will be carefully examined by federal authorities."

Despite the revelations, many Liberal MPs who spoke to Fairfax Media insisted Mr Guy retained their confidence.

Victorian Liberal Party president Michael Kroger told ABC Radio none of the dinner guests had made recent discloseable donations to the party or given smaller sums to his knowledge.

Labor ministers made repeated references to Beaumaris and accepting money from mobsters in question time at Parliament on Wednesday.

And Deputy Premier James Merlino released a list of 17 questions for Mr Guy, including asking exactly how many people attended the dinner and whether he would release all correspondence to the corruption watchdog.

Earlier in the week Mr Guy said he was so confident he had done nothing wrong he would refer the matter to the Independent Broad-based Anti-corruption Commission for investigation.

Opposition spokeswoman for children Georgie Crozier said the parliamentary party was united and strongly behind Mr Guy.

She insisted the revelations did not undermine the Coalition's strong campaigning on law and order in Victoria. "I think this is just white noise," she said.

Another opposition frontbencher, Ryan Smith, said Mr Guy could not have been more open about the dinner.

"His team sees that," he said.

Following the Coalition's 2014 election loss, shadow treasurer Michael O'Brien contested the leadership.

But on Wednesday Mr O'Brien insisted he supported Mr Guy to stay in the top job.

"Matthew Guy has done a great job in taking the fight up to Daniel Andrews on behalf of Victorians neglected by Labor," he said. "He will make a great premier and has my full support.

On Wednesday morning Coalition MPs including shadow energy minister David Southwick??? and Kew MP Tim Smith all said Mr Guy had their full backing.

"I'm behind him 1000 per cent," Tim Smith said. "He has my absolute support and he's doing a fantastic job."

Mr Southwick also stood by his leader.

"Matthew Guy has made his comments very clear here in terms of what has gone on. The situation really is that we need to get on with the real issues that matter in Victoria," he said.