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AUKUS (Australia, UK, US)
Sept 15, 2021· Alliance or organization
FactTreaties, membership, measured data, events.
A 2021 security pact under which the US and UK help Australia acquire nuclear-powered submarines and share advanced military technology.
See it on the Geopolitics map →The picture
Announced September 15, 2021, it made Australia only the second country, after Britain in 1958, to get US naval nuclear-propulsion secrets; the subs carry conventional weapons only. Australia scrapped a French submarine deal, angering Paris. Under the 2023 plan, US and UK subs rotate through Perth from 2027, Australia buys three to five US Virginia-class boats in the 2030s, then builds a new British-designed class. Cost: up to A$368 billion by the 2050s. 'Pillar 2' covers AI, hypersonics and quantum tech.
Why it matters
It binds Australia's defense to the US and UK for decades and extends allied undersea reach toward the South China Sea; China calls it a Cold War-style bloc.
Key facts and numbers
Leaders' statements of September 2021 and March 2023, Australian defence budget papers, the trilateral naval nuclear propulsion agreement, and the 2025 UK–Australia Geelong Treaty.
What to watch
Whether US shipyards can build enough submarines to sell Australia some while meeting US needs, a concern behind a 2025 Pentagon review, and whether costs and timelines hold.
Connections (2)
▸United Kingdom is a member of AUKUS (Australia, UK, US)Fact
The relationship
Britain supplies the design for the future SSN-AUKUS submarine, to be built by BAE Systems at Barrow-in-Furness for the Royal Navy and in Adelaide for Australia. A British sub will also rotate through Perth. For London, AUKUS anchors its post-Brexit tilt to the Indo-Pacific and sustains its submarine industry.
Since when and why
Announced September 15, 2021; the March 2023 San Diego plan; the 50-year UK–Australia Geelong Treaty, signed July 2025.
How we know
UK Ministry of Defence statements, BAE Systems contracts, and the published text of the Geelong Treaty.
What to watch
Whether Britain's strained defense budget and shipyards can deliver on time; its first SSN-AUKUS boat is due only in the late 2030s.
▸Australia is a member of AUKUS (Australia, UK, US)Fact
The relationship
Australia joined AUKUS in 2021, scrapping a French submarine deal, to get nuclear-powered submarines that can patrol far into Asian waters. It will buy three to five US Virginia-class boats from 2032, then build a British-designed class, at up to A$368 billion through the 2050s, and helps pay to expand US shipyards.
Since when and why
Announced September 15, 2021 by Scott Morrison, Joe Biden and Boris Johnson; plan set in San Diego, March 2023; endorsed by a Pentagon review in December 2025.
How we know
AUKUS agreements, the 2023 US law authorizing submarine sales, Australian budget papers and the Pentagon review's findings.
What to watch
Whether US yards, already too slow for their own navy, can spare submarines, and whether Australia cedes too much sovereignty; critics, including former Labor leaders, argue so.