Former prime minister Tony Abbott has predicted more MPs will be implicated in Parliament's ongoing citizenship fiasco, which has already eliminated six federal politicians and seen the major parties launch internal audits to weed out any others.
In the past week, Turnbull government frontbenchers Josh Frydenberg and Alex Hawke have been forced to deny they could have inadvertently acquired dual citizenship through their mothers. But Prime Minister Malcolm Turnbull has strongly resisted a Parliament-wide probe despite growing calls for a full-scale audit, including from Coalition MPs.
Mr Abbott said it was up to the Prime Minister to decide how to resolve the situation, but warned the government and country could not afford an "ongoing circus".
"Every day it's someone else. It was Josh last week, now it's Alex Hawke. It will probably be someone else tomorrow. That's why this matter does need to be resolved," he told radio station 2GB.
Mr Abbott's staunch ally Kevin Andrews, who was defence minister under the former leader, has called in recent days for an audit and questioned whether the Prime Minister was providing strong and decisive leadership.
After resisting a parliamentary audit, Labor has come around to a "universal disclosure" of citizenship documents and the Greens will move next week to establish a committee that could compel all senators to prove they have complied with section 44 of the constitution.
Days after the High Court ruled five MPs - including former deputy prime minister Barnaby Joyce - were invalidly elected, Senate president Stephen Parry also revealed his own British citizenship.
Last week, the government angrily rejected questions over the eligibility of Mr Frydenberg, the Energy and Environment Minister, whose mother arrived "stateless" as a Jewish refugee from Hungary. The central European country, which has since changed its laws to open citizenship to Jewish refugees, grants citizenship by descent.
Mr Hawke, the Assistant Minister for Immigration, has insisted he is in the clear despite his mother's Greek background. He said he was "an Australian citizen only and [has] never held or acquired or sought Greek or any other citizenship".
Over the last few months, the Liberal and Labor parties have been conducting internal audits that have required legal checks and MPs to hand over necessary documents.