The administration of Donald Trump said earlier this year it was reviewing a 2021 deal for the nuclear-powered attack subs signed under his presidential predecessor Joe Biden.

The Department of Defense completed its five-month review, which endorsed the AUKUS agreement and determined it is "in alignment with President Trump's America First agenda," Pentagon spokesman Sean Parnell said in a statement.

"Consistent with President Trump's guidance that AUKUS should move 'full steam ahead,' the review identified opportunities to put AUKUS on the strongest possible footing."

Congressman Joe Courtney, the top Democrat on a US House subcommittee on sea power, said the review's completion assures that the pact's "framework is aligned with our country's national security interest."

"With its completion, it is important to note that the 2021 AUKUS agreement has now survived three changes of government in all three nations and still stands strong."

Courtney is a vocal champion of AUKUS in Congress, and represents a Connecticut district that is home to the primary submarine manufacturing facility in the United States.

The AUKUS pact aims to arm Australia with a fleet of cutting-edge submarines from the United States and would provide for cooperation in developing an array of warfare technologies.

The submarines, the sale of which will begin in 2032, lie at the heart of Australia's strategy of improving its long-range strike capabilities in the Pacific, particularly against China.

The deal could cost Canberra up to US$235 billion over the next 30 years, and also includes the technology to build its own vessels in the future.

Australia had a major bust-up with France in 2021 when it canceled a multi-billion-dollar deal to buy a fleet of diesel-powered submarines from Paris and go with the AUKUS program instead.