The man behind a review into the AUKUS deal said the US was “optimistic but clear-eyed” about delivering three second-hand nuclear powered subs to Australia in the biggest sign yet the pact may be in trouble.

Elbridge Colby, the Pentagon’s policy chief, said the Trump administration had tight, private discussions with the Albanese government about AUKUS, and the Australians “know what…

Elbridge Colby says AUKUS is “full steam ahead” but didn’t guarantee Australia would receive three nuclear subs next decade.