Vice Admiral David Johnston will be tasked with seeing through the landmark AUKUS pact with Washington and London, a major military overhaul that will see Australia acquire nuclear-powered submarines.

Defence Minister Richard Marles said Johnston was the first navy officer to lead Australia's armed forces in more than two decades.

"In respect of acquiring a nuclear-powered submarine capability, and of modernising our service fleet, this will be a time when having someone from the navy in the top job will be very worthwhile," Marles told reporters.

Under the fledgling AUKUS deal, Australia, the United Kingdom and the United States have pledged to retool their militaries in a bid to counter China's rise.

The longtime allies will work to equip Australia with a fleet of potent nuclear-powered attack submarines -- one of the nation's biggest-ever military upgrades.

"David has been at the very heart of reshaping the Australian Defence Force," Marles told reporters.

"He has been in the engine room of all the work we have done over the last two years."

The AUKUS partners, in an attempt to further bolster the pact, have meanwhile been eyeing up increased military cooperation with Japan.

In a joint statement released overnight, they indicated a willingness to work with Japan on the development of advanced capabilities such as undersea drones and hypersonic missiles.

Johnston is a navy veteran of more than 40 years who has served in deployments to Fiji and the Middle East.