Embattled Victorian MP Cesar Melham has refused to comment on his future despite expectations he will stand down.

Mr Melham didn't stop to talk to reporters as he entered Parliament on Tuesday morning. But when asked if he had betrayed his former union members over a deal that allegedly short-changed cleaners he said "absolutely not".

Fairfax Media understands Mr Melhem was leaning toward resigning as upper house whip on Monday night as he prepared to face concerned colleagues in party room meetings on Tuesday morning.

In exclusive comments to Fairfax Media on Monday night, Mr Melhem said: "I am considering all options in the interest of the government."

A clearly distressed Mr Melhem confirmed he would be discussing his future with Premier Daniel Andrews, family and colleagues, before Tuesday's caucus meeting.

He said he would also attend a pre-caucus meeting at 8.45am with his own Right sub-faction linked to the AWU, including Roads Minister Luke Donnellan, Natalie Hutchins, Anthony Carbines, Danny Pearson, Shaun Leane, Jaclyn Symes and Natalie Suleyman.

Members of that group told Fairfax Media on Monday they hoped, and expected, Mr Melhem would voluntarily step down ahead of the ALP caucus meeting at 10am.

If Mr Melhem did not, caucus would consider removing him to avoid more damaging distractions.

A string of MPs also said they did not believe Mr Melhem could continue his role as convener of the AWU caucus group.

The controversy has cast a spotlight on Mr Andrews' leadership, given his failure to comment or act on the allegations currently being aired before the royal commission into union corruption.

Government MPs across the factions are furious with Mr Melhem after the royal commission heard allegations of a deal with a cleaning company that left workers on lower pay in return for cash payments to the AWU.

The commission also heard evidence last week of other deals where employers paid for AWU memberships, boosting the union's numbers and sway within the ALP.

To date, Mr Andrews has refused to act against Mr Melhem, repeatedly insisting he would not provide a running commentary on the royal commission, which Labor has slammed as a political witch-hunt.

Witch-hunt or not, in royal commission hearings last week Mr Melhem's successor, AWU secretary Ben Davis, described one of Mr Melhem's deals as "untoward".

The national AWU also said the evidence pointed to a "potential betrayal" of the union.

Labor MPs are already canvassing options to replace Mr Melhem as upper house whip, with right-faction MPs Philip Dalidakis, Jaclyn Symes and Daniel Mulino slated as possible options.

Mr Melhem, who replaced Bill Shorten as AWU state secretary in 2006, has strongly denied wrongdoing, telling the commission that in 23 years he had done nothing but improve conditions for workers.

Mr Melhem's evidence to the commission was also directly contradicted last week by one of Mr Andrews' key advisers, former AWU organiser John-Paul Blandthorn.

Upper house MP Shaun Leane emailed colleagues late last week saying Mr Melhem should to be dumped as the convener of the AWU section of the party room "given the ugly accusations levelled against him and the AWU national and state secretaries publicly removing support for him".

Mr Melhem's troubles started in December 2012 when The Age revealed details of an employer-bankrolled slush fund, Industry 2020, established by him as AWU secretary in 2008.

The Age revealed how the fund was used for interference in the elections for the disgraced Health Services Union, and for ALP branch-stacking.

Last year the royal commission quizzed Mr Melhem about Industry 2020, but then went further to probe questionable AWU deals with employers.