In a leaked message, Deputy Prime Minister Barnaby Joyce, who heads the junior partner in Morrison's coalition government, said last year that he had never trusted Morrison.
Australian Deputy Prime Minister Barnaby Joyce has apologised to Prime Minister Scott Morrison for calling him "a hypocrite and a liar".
"I want to apologise to the prime minister...I should have never written the text that I did," Joyce told a news conference on Saturday.
"My view from the backbench about the prime minister was based on assumption and commentary, not from a one-on-one working relationship."
He also said Morrison had rejected his offer to resign.
Morrison said in a statement that he accepted Joyce's apology.
In a leaked message, the deputy prime minister, who heads the junior partner in Morrison's coalition government, said last year that he had never trusted Morrison.
"He is a hypocrite and a liar from my observations and that is over a long time," Joyce wrote to a former staffer of Morrison's Liberal Party who had alleged sexual assault by a fellow staffer.
After Joyce's apology, Morrison responded, "Relationships change over time. Politicians are human beings too. We all have our frailties and none of us are perfect."
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Opposition Labor leader Anthony Albanese said it was "untenable" for Joyce to continue as deputy prime minister.
"I couldn't care less that the Liberal Party members all don't like each," Albanese said at a briefing.
"What I do care about is the consequences of a government that is dysfunctional."
Joyce's text message, first reported on Friday night by Nine Newspapers, was sent through a third party to former Liberal Party staffer. She had alleged she was sexually assaulted in Parliament House in March 2019.
Joyce's remarks further shake the political position of Morrison, who must call a federal election by May. His approval ratings have fallen over his handling of an Omicron-driven coronavirus outbreak.
Joyce became deputy prime minister in 2021 as the leader of the National Party, not as Morrison's appointee.
Joyce's party, which has the power to remove him as its leader, said it would not be commenting beyond Joyce's statement.
The political commotion comes days after a controversy about an alleged exchange between senior Liberal Party members making derogatory remarks about Morrison.
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