A US review of a deal to provide Australia with nuclear submarines is routine, the defence minister says, despite calls for a backup plan in case the Trump administration scraps AUKUS.
The Pentagon on Thursday announced a review of the three-nation pact that would give Australia nuclear submarines, to see if the agreement lined up with President Donald Trump's "America First" agenda.
But Defence Minister Richard Marles has downplayed the significance of the review, saying it's standard procedure.
"We engaged with the United Kingdom when they did their review, which is perfectly natural, and of course, when we did the defence strategic review, we also went to both the United States and the United Kingdom and sought their views," the acting prime minister told ABC Radio on Monday.
"It's a pretty natural process that we all engage in each other's reviews.
"We'll engage with the reviews and the (US) Department of Defense about how AUKUS is tracking in Australia."
The AUKUS deal is set to be raised when Prime Minister Anthony Albanese meets with Mr Trump for a one-on-one meeting on the sidelines of the G7 meeting in Canada on Tuesday.
The American review has prompted calls for the federal government to consider a contingency plan in the event the submarine deal is called off.
One-time coalition deputy prime minister Barnaby Joyce said the US review was a concern.
"You should have a contingency plan, as soon as the United States said 'we're reviewing AUKUS', alarm bells should have rung everywhere," he told Seven's Sunrise program.
"We absolutely should have a contingency plan, but I haven't heard of any contingency plan."
Under the $368 billion program, Australia will buy at least three Virginia-class submarines from the US sometime in the early 2030s.
A new class of nuclear submarines will be built in Adelaide to be delivered in the 2040s.
Former Australian ambassador to the US Arthur Sinodinos said he was confident AUKUS would survive.
"There's a lot of bipartisan support for the deal, from day one in the (US) Congress, both Republican and Democrat," he told the Seven Network.
"Trump himself would see that we're pulling our weight, we're going to spend $370 billion."
Mr Sinodinos, who was ambassador when the deal was announced in 2021 under then-prime minister Scott Morrison, said if the US backed away from the agreement, that would play into the hands of China.
"If we look at any stage like we're second guessing ourselves, or we're not committed to really doing this ... the Chinese will say, 'well, look at the end of the day, they're all paper tigers'," he said.
"The Americans see that by having more subs actually built in the region, and being serviced in the region, that enhances their capacity to do things in the region.
"We don't need a plan B."