A former Australian assistant defense secretary says there might be more Marines in Australia in the wake of a new trilateral defense alliance.

AUKUS, which officials had been talking about for the past 18 months, is about much more than submarines, Babbage said.

“We are going to see larger U.S. forces coming, including U.S. Army forces and air power coming here on rotation,” he said. “It’s quite likely the Marine Corps presence could be scaled up.”

The U.S. Embassy in Canberra and the Australian Defence Department did not respond Friday to questions about the possible effect of the trilateral defense pact on the Marine rotations.

About 2,200 US Marines expected in Darwin in the 2021 rotation as Canberra also eyes improved air, maritime capability.

Outlining further measures on a visit to Washington, Defence Minister Peter Dutton said on Thursday that Australia will be “significantly enhancing” cooperation including working together on the development of missiles and explosive ordnance.

He said Australia was willing to see more US Marines in a 10-year rotation through the northern city of Darwin.

“I do have an aspiration to make sure that we can increase the numbers of troops through the rotations,” Dutton said.

Australia's new strategic alliance with the United States and United Kingdom is likely to see more troops, war planes and naval vessels in the Top End. But any expansion could be hindered by the controversial lease of Darwin Port to a Chinese company, national security experts say.

Heralded as the most significant shift in Australia's defence direction in decades, the centrepiece of the trilateral security partnership, dubbed "AUKUS", is a plan to build a fleet of nuclear-powered submarines.

But Defence Minister Peter Dutton has also flagged a major enhancement in Australia's military cooperation with the US, which currently deploys about 2,500 marines to the Top End each dry season.

John Coyne from the Australian Strategic Policy Institute said the 99-year lease of the Darwin Port to Landbridge could prove an impediment to the allies' military expansion plans.

WASHINGTON: Australia said Thursday that more US troops will rotate through the island nation and that the allies will cooperate on missiles, the latest joint steps amid shared concerns over a rising China.

Outlining further measures on a visit to Washington, Defense Minister Peter Dutton said Australia will be “significantly enhancing” cooperation including working together on the development of missiles and explosive ordnance.

He said Australia was willing to see more US Marines in a decade-old rotation through the northern city of Darwin

US Defense Secretary Lloyd Austin, also without giving numbers, confirmed that the United States “will expand our access and presence in Australia.”

Australia is open to boosting American troop rotations and increasing military plane visits as defence co-operation between the allies ramps up.

A historic pact to share nuclear-powered submarine technology - under the umbrella of a new alliance known as AUKUS - has been signed as Australian ministers held talks with counterparts in the United States.

Foreign Minister Marise Payne and Defence Minister Peter Dutton met with US Secretary of State Antony Blinken and Defense Secretary Lloyd Austin on Friday morning for the latest AUSMIN talks.

Mr Dutton said he aspired to increase troop rotations and other military co-operation between the two nations.

"If that includes basing and includes the storage of different ordinances, I think that is in Australia's best interests, in our national interests at this point in time."