Australia's claim it couldn't consult France about torpedoing a $90 billion submarine contract has been labelled "childish" by the European nation's returning ambassador.
Ambassador Jean-Pierre Thebault is returning to Canberra after being recalled over the shock announcement that infuriated the French.
But he says France doesn't know if it can trust Australia after being lied to, and cast doubt on whether the two governments were still friends.
"This remains to be seen. That's exactly the reason for which I have been instructed to come back," Mr Thebault told ABC radio on Friday.
"Confidence is not something you throw away when it's convenient. Trust is something you build, trust is something you create through your own action."
Australia scrapped its 2016 agreement for 12 conventional vessels from Naval Group in favour of access to technology for nuclear-powered submarines under the AUKUS pact with the US and UK.
Prime Minister Scott Morrison insists it was impossible to avoid secrecy.
But Mr Thebault pointed to US concessions the deal could have been better handled.
"It's childish to say that it was impossible to consult France," he said.
He said America had officially stated things should have been done differently including greater consultation.
Mr Thebault will look at the implications for jobs in both Australia and France upon his return to Canberra.
The ambassador stresses serious preparation is needed before Mr Morrison and French president Emmanuel Macron can speak.
"If we see that we can make the necessary progress in order to re-establish trust, to re-establish confidence between our two governments, then we can move forward," he said.
"Let's not be in a situation where one will say, 'I talked to the other and I pretend I said that' and the other will say 'but I didn't hear that'. No, let's prepare seriously."
He said the problem was bigger than a submarine contract, amounting to a "deep crisis" of political and security cooperation.
Malcolm Turnbull, who was prime minister when the French deal was signed, accused his successor of double-crossing the French.
"They will never trust Scott Morrison. We just have to hope that in future they will be able to trust another prime minister," he said.
"But Morrison has deceived them so blatantly and so shamelessly, they obviously are not going to trust him.
"The best I can say to Macron and to others in France is this: We may have a deceitful prime minister, but believe us, we are not a deceitful nation."
Australian Associated Press
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