Australia's assertion that it could not inform France of its top-secret talks with the United States and Britain to build nuclear submarines is "childish", the French envoy to Canberra said on Friday.

Australia walked away from a US$40 billion deal with France's Naval Group to build a fleet of conventional submarines last month and will instead build at least eight nuclear-powered submarines with US and British technology after striking a trilateral security partnership with those two countries.

The cancellation angered France, which accused...