French President Emmanuel Macron has called Australia’s Prime Minister Scott Morrison a liar on the world stage.

In an extraordinary doorstop interview with Australian reporters at the G20 in Rome, Macron was asked if he thought Morrison lied to him over the cancellation of a submarine contract in September. The French President’s reply was damning:

I don’t think, I know.

For his part, Morrison says he did not lie (and gave Macron a heads-up in June about the contract). Nevertheless, the comments show a diplomatic relationship in deep trouble.

Macron’s comments come off the back of Australia’s abrupt strategic breakup with France as part of the AUKUS partnership. In September, Australia announced this new alliance, which meant it would end a multibillion-dollar submarine deal with France.

This sudden decision greatly angered the French, who have likened it to a “stab in the back”.

As a result, France cut off diplomatic communication. This only resumed on October 28 with a frosty phonecall between Macron and Morrison. The recently concluded G20 meeting in Rome was their first meeting in person since the tensions emerged.

As the tensions swirled, Morrison approached the French President unannounced at the Rome summit, while Macron was talking to others. Morrison put his arm on the President’s shoulder and reportedly said “g’day”. Images were then released by Morrison’s office as proof of the functional relationship between the two leaders.

The next day, Macron answered Australian reporters’ questions as he was leaving a press conference. Macron’s informal comments, at such a highly choreographed diplomatic event, show how he went out of his way to show he and Morrison are not mates on “g'day” terms.

Macron also took these further steps to ensure his message did not get lost in translation:

He made the comments in English. The French President speaks English but usually uses French, the language of the republic he represents. Using English was a way of speaking to Australians directly, rather than having a voiceover doing a translation from the French.

He spoke to the media of a foreign country – usually a world leader would not engage informally with media from other countries. This is done formally, at joint press conferences.

He did not use “diplo-speak”. Macron is a highly educated, polished politician who knows how to choose his words and send subtle messages. This message was deliberately blunt.

Since the September fallout, France recalled its ambassador from Canberra to “re-evaluate” its relationship with Australia. In French diplomatic language, “re-evaluate” is a powerful euphemism. All forms of cooperation (military, political, educational, cultural) are at a standstill.

As of January 2022, France will take on the presidency of the Council of the European Union for six months. The timing could not be worse for Australia as it tries to negotiate a major trade deal with the EU. Negotiations have already been paused for a month as a result of the failed submarine deal. The economic implications are serious for Australia, which has a lot more at stake than Europe here. The EU is Australia’s third-largest market but Australia is only the EU’s 19th-largest trading partner.

Indeed, Australia is a sensible target for France to send signals to any other allies that may be tempted to act against French interests. As a middle power, Canberra can be treated as a naughty child in a way that more powerful allies, such as the United States, cannot.

Macron has made it clear he respects Australia, its people, and its shared values with France.

But his comments also show it will be very hard to properly repair the bilateral relationship while the two men are in power. Fundamentally, Macron says he does not trust the current Australian prime minister.

What is urgently needed is for French and Australian diplomats and high-level officials to start talking again, because so much more is at stake than submarines. If they do, this will mean the infrastructure is there at the working level, when leaders are able to engage properly again. Regrettably, this may not happen for a while.