A backroom powerbroker has resigned from the Liberal Party in Victoria over a branch-stacking scandal.
Pressure is now building on two senior federal politicians tied to the affair as party officials in Victoria more to appoint forensic accountants to review the party's membership records.
Marcus Bastiaan allegedly directed taxpayer-funded electorate officers to recruit party members and stack Liberal branches with conservatives.
The right-wing operatives reportedly targeted ethnic communities and religious groups.
Mr Bastiaan denies the branch-stacking claims but has quit the Liberals regardless.
"The ongoing leaking of years-old historic material is an unnecessary distraction from the Liberal Party and it is with that in mind that I have resigned," he said in a statement on Monday.
The allegations exposed by Nine's 60 Minutes program date back to 2016.
Assistant Treasurer Michael Sukkar and veteran MP Kevin Andrews are both feeling the heat after their offices were linked to the allegations.
Victoria's Liberal Party director Sam McQuestin has demanded answers from both men.
The pair have denied any wrongdoing and ordered independent reviews of their staffing arrangements.
Mr McQuestin said in a statement that a meeting of the party's administrative committee on Monday night resolved to appoint forensic accountants to review the party's membership records, practices and rules.
"This move further demonstrates the Liberal Party's commitment to ensuring the integrity of our party's membership and systems," he said.
Prime Minister Scott Morrison is under pressure to act on the matter after leading the charge against branch-stacking claims within the Labor Party earlier this year.
Labor is demanding Mr Sukkar resign from the ministry and Mr Andrews also be sanctioned.
"We know what Scott Morrison thinks of branch stacking. In June this year he had a very clear view. He called it corruption," Labor frontbencher Stephen Jones told reporters in Canberra.
"Scott Morrison should move to sack Michael Sukkar today."
Mr Morrison has argued the allegations are a matter for the Victorian branch.
Victorian opposition leader Michael O'Brien said the Liberal Party would be better without Mr Bastiaan.
He would not be drawn on whether Mr Sukkar and Mr Andrews should stand down while investigations take place.
"That's entirely a matter for the prime minister," Mr O'Brien told reporters in Melbourne.
"I've made very clear that we want to make sure that the Liberal Party is a party which actually lives its values.
"What we saw last night was as far away from Liberal Party values as I could imagine."
Secret recordings and text messages aired by 60 Minutes also exposed plans to oust moderate state and federal politicians.
Mr O'Brien said federal MPs should keep out of state preselections.
Treasurer Josh Frydenberg, the most senior Victorian Liberal, is standing by his party colleagues.
Mr Frydenberg said concerning conduct exposed by the program would be investigated internally.
He said it was also appropriate for the Department of Finance to examine the staffing claims.
Branch-stacking revelations that shook the Victorian Labor Party in June cost the scalps of three state government ministers.
Australian Associated Press