John Howard backs Scott Morrison following secret portfolios scandal

Mr Morrison is under pressure to resign from Federal Parliament after revelations he secretly seized control of five major portfolios during the pandemic.

"I don't think it's something that is so reeking with principle as to require an unwanted, expensive, unnecessary by-election," Mr Howard told ABC's 7.30 on Tuesday night.

"There are reasons why he did it. And part of the conservative tradition is to always understand the context.

"Apart from anything else, it's not in the interests of the Liberal Party - a by-election at the moment, in a very safe seat - particularly as in the state of New South Wales we will face a state election in the early part of next year."

Earlier on Tuesday, former home affairs minister Karen Andrews accused Mr Morrison of a "betrayal of trust" and has called on him to quit politics, after he appointed himself to the portfolio without telling her or the public.

However, 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".

Mr Morrison has apologised to his colleagues "for any offence" but insisted he took the unprecedented decisions in "good faith".

The former prime minister said he only used the powers once - to scuttle a controversial gas exploration permit off the NSW coast while secretly serving as resources minister.

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