Alliance · Security pact

AUKUS

Australia, the United Kingdom and the United States

AUKUS is a security partnership of Australia, the United Kingdom and the United States, announced on September 15, 2021. Its main project will give Australia nuclear-powered submarines carrying conventional weapons, with the first due in 2032. A second strand develops military technology such as undersea drones, artificial intelligence and hypersonic missiles. AUKUS has no mutual-defense promise and no headquarters.

Updated October 2026 · Joint statements of the three governments and Australia's Defence department

Albanese, Biden and Sunak present the submarine plan in San Diego, March 13, 2023. Photo: the White House, public domain.

Members: 3; Announced September 2021
First submarine: 2032; A used US Virginia-class
Planned fleet: 8; Nuclear-powered, by the mid-2050s
Cost to Australia: A$268-368bn; 2023 estimate, to 2055
Defense promise: None; Not a military alliance

Which countries are in AUKUS?

AUKUS has three members: Australia, the United Kingdom and the United States. Its name joins their initials. Prime Minister Scott Morrison, Prime Minister Boris Johnson and President Joe Biden announced it by video link from Canberra, London and Washington on September 15, 2021. In Australia it was September 16. The three had met at the G7 summit in Cornwall on June 12, 2021. The official account did not mention submarines. Morrison kept the plan from most of his national security cabinet. He said it was handled "on a 'who needed to know' basis."

No other country has joined. In 2024 the three began consulting Japan, Canada, New Zealand and South Korea on technology projects. In March 2026 Canada's defense minister said joining was "not something we have pursued at this stage." New Zealand says it is waiting for advice from the three members.

World map. The three members of AUKUS are blue: the United States, the United Kingdom and Australia.

Is AUKUS a military alliance?

AUKUS is not a military alliance. It was created by a joint statement, not by a treaty, and none of its documents commits the members to defend each other. Its treaty-level agreements cover nuclear propulsion. One, signed on August 5, 2024 and in force since January 17, 2025, allows the United States and Britain to transfer naval reactors and nuclear fuel to Australia.

Before AUKUS, the United States had shared its naval nuclear propulsion technology only once, with Britain. A US official said in 2021 that it happened "almost 70 years ago." President Biden called the boats "conventionally armed submarines that are powered by nuclear reactors." Prime Minister Morrison said: "Australia is not seeking to acquire nuclear weapons."

We are announcing the creation of an enhanced trilateral security partnership called 'AUKUS'.

Joint statement of the leaders of Australia, the United Kingdom and the United States, September 15, 2021

Australia and the United States

ANZUS, since 1951

A treaty that also includes New Zealand. Each side would "act to meet the common danger" if another is attacked in the Pacific.

Britain and the United States

NATO, since 1949

Their mutual-defense promise covers attacks in Europe and North America. It does not extend to Asia or the Pacific.

Britain and Australia

Geelong Treaty, 2025

A 50-year treaty on designing, building and running submarines, in force since December 2025. It is not a defense pact.

How will Australia get nuclear-powered submarines?

The three leaders set out three steps in San Diego on March 13, 2023. From 2027, US and British submarines rotate through HMAS Stirling near Perth. Australia buys three used Virginia-class submarines from the US Navy in 2032, 2035 and 2038. Then comes SSN-AUKUS, a new British design with US technology, with Australia's first, built in Adelaide, in the early 2040s. The target is a fleet of eight boats by the mid-2050s.

Australia's government estimates the cost at A$268 billion to A$368 billion to 2055, about 0.15% of GDP a year. The main risk is US shipbuilding. American yards produce about 1.1 to 1.3 Virginia-class boats a year, against 2.33 needed. US law requires the president to certify, at least 270 days before each sale, that it "will not degrade" US undersea strength.

Australia's submarine plan

2021AUKUS is announced and the French submarine deal cancelled
2023Submarine plan presented in San Diego
2027US and British submarines begin rotating near Perth
2032First used Virginia-class submarine from the US Navy
2035Second used Virginia-class submarine
2038Third used Virginia-class submarine
2040sFirst SSN-AUKUS built in Adelaide
2050sA fleet of eight nuclear-powered submarines

Why was France angry about AUKUS?

AUKUS ended a French submarine deal with Australia. In April 2016 Australia chose the French company Naval Group to design 12 diesel-electric submarines. Australia's defense department estimated the program at A$89 billion by January 2021. On June 15, 2021 President Emmanuel Macron hosted Prime Minister Morrison for dinner in Paris. The French side had no hint that the deal would be cancelled. Two days before the announcement, Macron texted Morrison: "Should I expect good or bad news for our joint submarine ambitions?"

The French embassy in Washington cancelled a gala for the 240th anniversary of the Battle of the Capes of 1781. In that battle the French navy defeated the British, helping win American independence.

The lost contract€56 billion

French media valued the cancelled deal at €56 billion. Australia's full program estimate also covered its own shipyards and weapons systems.
"A stab in the back"Sept 16, 2021

France's foreign minister, Jean-Yves Le Drian, said on French radio: "I am angry, this is not done between allies."
Ambassadors recalledSept 17, 2021

France called home its ambassadors to Washington and Canberra, a first. It left its ambassador in London, calling Britain the "fifth wheel."
"I don't think, I know"Oct 31, 2021

President Macron's answer, in English, when reporters at the G20 in Rome asked whether Prime Minister Morrison had lied to him. Morrison denied it.
Settlement€555 million

Paid to Naval Group in June 2022 by Morrison's successor, Prime Minister Anthony Albanese. Australia spent A$3.4 billion on the French program in all.

What else does AUKUS do?

AUKUS has a second part, called Pillar II, that develops military technology. It covers eight areas: undersea capabilities, quantum technologies, artificial intelligence and autonomy, advanced cyber, hypersonic and counter-hypersonic weapons, electronic warfare, innovation, and information sharing. In February 2026 an exercise off Australia's east coast tested about 30 uncrewed systems with more than 200 personnel.

AUKUS survived a change of US president. In June 2025 the Pentagon began reviewing AUKUS against President Trump's "America First" agenda. On October 20, 2025, at the White House, Trump told Prime Minister Albanese: "we're just going now full steam ahead building." In December 2025 the Pentagon said the review found ways to put AUKUS "on the strongest possible footing." The findings were not published.

Pillar II projects

Tracking submarines with AISince 2023

Shared artificial intelligence on P-8A patrol planes reads data from sonar buoys dropped in the sea to find submarines.
Undersea dronesFrom 2027

The first joint "Signature Project," agreed in May 2026. It provides equipment for uncrewed submarines, with deliveries from 2027. Britain is contributing £150 million.
Hypersonic testsUp to 2028

Up to six joint flight-test campaigns of hypersonic missiles by 2028, with a fund of $252 million.
Arms trade without licensesSince 2024

Since September 1, 2024 a US exemption lets much defense trade among the three skip export licenses. The exclusion list is being narrowed.
A torpedo from a droneSept 2026

The Royal Navy's uncrewed submarine Excalibur fired a US practice torpedo, with no warhead, at a test range in Scotland.

Is it in AUKUS?

Short answers for the countries people ask about most.

Is New Zealand in AUKUS?

Its 1987 nuclear-free law bans nuclear-powered ships from its internal waters, including ports. It was consulted on Pillar II but has not decided.

Is Canada in AUKUS?

Consulted on Pillar II in 2024. In March 2026 its defense minister said Canada was not pursuing membership.

Is Japan in AUKUS?

Consulted on Pillar II since 2024. In July 2025 Japan took part in an AUKUS experiment with uncrewed maritime systems.

Is France in AUKUS?

AUKUS ended France's contract to design Australia's submarines. Australia paid the French company Naval Group €555 million in 2022.

Is India in AUKUS?

India is in the Quad with the United States, Japan and Australia, a separate group with no mutual-defense promise.

Is South Korea in AUKUS?

Consulted on Pillar II since 2024. In 2025 the United States separately approved South Korea's own plan for a nuclear-powered submarine.

Is China in AUKUS?

China's foreign ministry called the submarine deal "extremely irresponsible" in 2021. China raises AUKUS at every meeting of the IAEA's board.

Is Indonesia in AUKUS?

In 2021 Indonesia said it was "deeply concerned" about an arms race in the region. Its tone softened by 2023.

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