Former prime minister Malcolm Turnbull has blasted his successor's "shameful" and "duplicitous" behaviour towards France over a scrapped $90 billion submarine deal.
Mr Turnbull's comments came after Scott Morrison said he wouldn't cop any "sledging of Australia" after French President Emmanuel Macron labelled him a liar.
The prime minister maintained Mr Macron knew there were problems with the Naval Group project before Australia announced it was torpedoing it.
But Mr Turnbull, under whom the 2016 contract for the Attack Class vessels was signed, thinks Mr Morrison owes the French an apology.
"He did very elaborately and duplicitously deceive France," Mr Turnbull told ABC radio on Tuesday.
"When you're dealing with people, honestly - and Scott Morrison did not do that - you don't drop hints. You actually tell the truth.
"It was a partnership between two nations, it was a cornerstone of France's Indo-Pacific strategy and to be double-dealing them the way Morrison did was shameful."
Mr Macron told Australian journalists at the G20 summit on Sunday, "I don't think, I know" the prime minister lied to him about the submarines.
Mr Morrison retaliated on Monday, detailing problems with the program during a news conference at the COP26 climate summit in Glasgow.
"I can deal with that. But those slurs, I'm not going to cop sledging at Australia. I'm not going to cop that on behalf of Australians," he told reporters.
Opposition Leader Anthony Albanese took aim at Mr Morrison for conflating criticism of his handling of the deal's cancellation with criticism of Australia.
"(Scott Morrison) is not the state of Australia. (He is) using our nation as a human shield," he said.
Australia in September announced it was cancelling the 2016 contract to acquire conventional Attack Class submarines from France's Naval Group.
Mr Morrison said he made it "very clear" to Mr Macron in June the conventional diesel-powered submarines were not going to meet Australia's strategic requirements.
"We discussed that candidly. I did not discuss what other alternatives we were looking at," he said.
"It's no secret, I'm sure in Australia, that this was a project that had few friends, and that is a point that we had made to Naval and particularly to the French government.
"It's clear from President Macron's statements yesterday that the level of offence is still very great and we will wait for that to subside."
The government will now spend the next 18 months looking at the feasibility of acquiring technology for nuclear-powered vessels from the United States and United Kingdom under the AUKUS partnership.
Communications between the two leaders were also leaked to the media, with the French president reportedly telling Mr Morrison, "I don't like losing".
Days before the announcement, Mr Macron reportedly messaged Mr Morrison asking, "Should I expect good or bad news for our joint submarine ambitions?"
Mr Albanese said the leaking of the text messages highlighted how the prime minister was treating international partners as political opponents.
"Gaslighting and backgrounding is no way to build relations with our important democratic neighbours," he said.
"Diplomacy requires trust and sombre engagements between leaders".
Australian Associated Press
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