Canberra chose a French design for its next-generation submarine fleet partly because it can easily be refitted for nuclear propulsion by the time the vessels enter service, an influential Australian business daily has reported.

Japan proposed a diesel-powered design based on its Soryu-class sub, which Tokyo believes is one of the quietest in the world.

But Australia wanted the option of converting some of its 12 planned attack submarines from diesel to nuclear, the Australian Financial Review reported on its website Sunday, quoting unnamed political, government and industry sources.