Scott Morrison taking on five portfolios in secret has been branded crazy and dodgy by Labor frontbencher Jason Clare.
The repercussions of the former prime minister appointing himself to the finance, treasury, health, home affairs and resources portfolios remain unknown and the solicitor-general is preparing advice for the prime minister to be delivered on Monday.
He was sworn in to the roles between March 2020 and May 2021.
"It's wrong in principle the former prime minister did this at all. It's made worse by the cover-up, the secrecy. It's something that never happened before and shouldn't happen again," Mr Clare told the ABC on Wednesday.
"This is mind boggling stuff, crazy stuff. The fact this was kept secret tells you that they knew this was dodgy as buggery."
Mr Clare also took aim at the Liberals defending Mr Morrison's actions after Opposition Leader Peter Dutton sought to justify the appointments due to the "war-like" environment of the COVID-19 pandemic.
"We heard yesterday some pretty weak mealy-mouthed excuses by Scott Morrison's colleagues, including Peter Dutton, saying we were in the teeth of a pandemic and these were war-like situations," Mr Clare said.
"We've been to war and we never did this. When war broke out in Europe, Menzies didn't do this. When the Japanese were on the march on the way to Port Moresby, John Curtin didn't do this."
Mr Clare told AAP the government will wait for the solicitor-general's advice before deciding how to prevent something similar happening in future, such as making it mandatory to gazette such appointments.
"We're open to reform," Mr Clare said.
"I expect cabinet will consider both the advice from the department and any advice we receive from the solicitor-general and then take further steps."
Prime Minister Anthony Albanese said the actions of his predecessor followed a pattern of secrecy.
"Scott Morrison appointed himself to a cabinet committee of just one so any meetings he had with other people he could say they were co-opted and keep it away from freedom of information," he told radio 4BC.
"Our democracy relies on people being open and transparent about what's going on (and) people being accountable and that's why this is such a shocking series of revelations."
Deputy Liberal leader Sussan Ley attacked the prime minister for not focusing on the cost of living and skills shortages.
"The fact this is featuring so heavily today is a strong indictment on the focus and priorities of Mr Albanese. He came back from a week's holiday and on day one, focused on his old job of opposition leader," she told Sky News.
"Australians want him to focus on the issues in their lives. Nothing in this is going to bring down your power bills."
Mr Morrison has apologised to his colleagues for having secretly sworn himself into their portfolios but launched a staunch defence of his actions.
The embattled former prime minister took to Facebook to explain himself, saying in hindsight some of the arrangements were unnecessary.
Meanwhile, former home affairs minister Karen Andrews called on Mr Morrison to resign from parliament.
"The Australian people have been let down, they have been betrayed," she said on Tuesday.
Former deputy prime minister Barnaby Joyce added while it wasn't illegal, he should've been informed about the extent of Mr Morrison's move, only being aware of the move in Keith Pitt's resources portfolio.
"Do I think it's the right thing to do? No it's not, why? Because we have a cabinet system of government," he told the ABC.
"Its better that the deputy PM (is informed). We had numerous discussions about it ... (but) the minister is the person that should have carriage of these issues."
© AAP 2022