Former home affairs minister Karen Andrews has declared Scott Morrison has blindsided her and is calling on him to resign from parliament after revelations he secretly appointed himself to her portfolio during the pandemic.
However the Opposition Leader Peter Dutton and former deputy prime minister Michael McCormack have defended their former leader.
Prime Minister Anthony Albanese has described the revelations that Mr Morrison secretly appointed himself as joint minister in health, finance, treasury, home affairs and the industry, science and resources portfolios as an "unprecedented trashing of our democracy".
Ms Andrews has told The Canberra Times that Mr Morrison had betrayed the trust of the Australian people by his actions.
"I had no idea he had been sworn in as the minister of home affairs, that he had been sworn into the portfolio that I held," she said.
"I heard about that only from media reporting today [Tuesday]. There seems to be without doubt a number of portfolios to which the former prime minister had himself sworn into.
"It is unacceptable for a prime minister to do that and basically subvert cabinet processes. For him not to have discussed it with me as the minister responsible for home affairs at the time, I believe is unacceptable and it is a betrayal of trust that the people of Australia put in him to lead the government.
"I think he should resign and he should leave parliament. This is unacceptable conduct," she said.
It comes amid tensions over the election day stunt, when the Home Affairs Department let go of long-standing conventions by revealing details about the arrival of an asylum seeker boat from Sri Lanka while the operation was underway.
Ms Andrews said she was told to publicise the operation by Mr Morrison.
Mr Dutton has urged calm as investigations continue.
"I think frankly it's time for cooler heads to prevail," he told reporters in Tasmania.
"The Prime Minister's come out of his holiday swinging and, obviously, this is an issue that he'll get his teeth into. But there are bigger issues that, frankly, the families of Australia are dealing with at the moment. So let's wait for the Prime Minister's process."
Mr McCormack, who was Nationals leader and deputy prime minister at the start of the pandemic, said Mr Morrison made the right calls to keep Australians safe.
He also defended the secrecy surrounding the appointments, which meant even he was in the dark about all but one of the portfolios [health] which Mr Morrison handed himself.
"There was a lot of moving parts and what we didn't want to do was make sure that the public was unnecessarily alarmed or panicked," he said.
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