CANBERRA: Australia's Prime Minister Scott Morrison said on Friday he doesn't believe he has lied since he was elected to parliament in 2007, rejecting allegations from French President Emmanuel Macron and others.

Macron this month said Morrison had lied to him over Australia's decision to scrap a multibillion-dollar deal with France to build Canberra's new fleet of submarines.

Criticism of Morrison intensified this week when he announced his government would spend A$178 million ($129.6 million) to support electric vehicles, three years after he criticised the technology.

But when asked on Friday, Morrison rejected allegations he had lied.

"No, I don't believe I have, no," Morrison told 3AW Radio. "It's politics. People take sledges at me all the time … I've learned in public life over a long period of time to not have a thin skin, to not get bitter."

Morrison can ill-afford to have his integrity called into question as he has to return to the polls by May 2022.

Widely watched polls show Morrison's coalition government trailing the opposition Labor party, while a Guardian Essential poll published this week showed voter approval of the prime minister at its lowest level in 18 months.

The poll showed Morrison's approval rating has fallen from a high of 65% in Febuary and now stands at 48%.

Allies too have also questioned whether they can trust Morrison, with the EU President Ursula von der Leyen earlier this year questioning whether the bloc could strike a trade deal with Australia until trust is repaired.

In solidarity with France, the European Union last month postponed the next round of talks on a free trade deal for a second time.

France has said Australia did not attempt to inform it of the cancellation until the day Canberra announced its deal with the United States and Britain. Morrison denies that, and messages he sent to Macron in the week before the announcement have since been leaked to local media.