France has recalled its ambassadors to the United States and Australia in the worsening row over their nuclear submarine deal.
French foreign minister Jean-Yves Le Drian said the "exceptional decision" was justified by the "exceptional gravity" of the actions of the two Western allies.
It followed the announcement earlier this week that the US and the UK had agreed to help the Australian navy acquire for the first time a fleet of nuclear-powered submarines.
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The development of the new fleet is the first of several tasks on the agenda for the new AUKUS partnership, leaders announced.
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The defence pact between the UK, US and Australia has been widely seen as an attempt to counter the growing military assertiveness of China in the Indo-Pacific region.
To the fury of Paris, the decision meant the cancellation of a £47bn deal for France to supply conventional diesel-electric submarines to the Australians.
Mr Le Drian made no mention of recalling the French ambassador to London – suggesting the French regard the US as the prime movers in the deal.
In his statement, Mr Le Drian – who had previously accused Canberra of a "stab in the back" – said he was acting on the instructions of President Emmanuel Macron.
"This exceptional decision is justified by the exceptional gravity of the announcements made on September 15 by Australia and the United States," he said.
He said their actions constituted "unacceptable behaviour between allies and partners, whose consequences directly affect the vision we have of our alliances, of our partnerships and of the importance of the Indo-Pacific for Europe".
The Australian government on Saturday expressed "regret" over France's decision.
A spokesperson for Minister for Foreign Affairs Marise Payne said in a statement: "We note with regret France's decision to recall its Ambassador to Australia for consultations following the decision on the Attack Class project.
"Australia understands France’s deep disappointment with our decision, which was taken in accordance with our clear and communicated national security interests.
"Australia values its relationship with France, which is an important partner and a vital contributor to stability, particularly in the Indo-Pacific. This will not change.
"We look forward to engaging with France again on our many issues of shared interest, based on shared values."