The French ambassador to Australia was in a car heading to Sydney airport for an urgent flight back home when he revealed he was “sad like any decent person would be”.

Jean-Pierre Thebault left Australia on Saturday night after Australia’s $90bn submarine deal with France was scrapped late last week, causing an unexpected rupture in the relationship between two friendly countries.

“I’ve seen and learned how deep for an Australian it is when you commit to watch each other’s back. What makes me sad is that we thought we were mates and we were stabbed in the back,” Thebault told Guardian Australia on the way from Canberra to Sydney airport.

The experienced diplomat was recalled to Paris, along with his counterpart in Washington, as the French government weighs up how to respond to what Biden administration officials called “the biggest strategic step that Australia has taken in generations”.