What's happened
On July 25, 2025, Australia and the UK signed a 50-year treaty in Sydney to deepen military cooperation, focusing on nuclear-powered submarines under the AUKUS framework. The US, currently reviewing the pact for alignment with its "America First" policy, is not a party to this bilateral treaty. The deal includes Australia acquiring Virginia-class submarines from the US and co-developing new submarines with the UK.
What's behind the headline?
Strategic Realignment in Indo-Pacific Security
The 50-year treaty between Australia and the UK marks a significant deepening of bilateral defense ties independent of the US, reflecting shifting dynamics within the AUKUS alliance. While the US remains a critical partner, its ongoing review under the "America First" agenda introduces uncertainty about its future role, prompting Australia and the UK to solidify their cooperation.
Implications of the US Review
The Pentagon-led review, directed by Defense Secretary Pete Hegseth and overseen by Elbridge Colby, signals potential recalibration of US commitments. This could delay or alter the delivery of Virginia-class submarines to Australia, forcing Canberra and London to consider greater self-reliance in submarine development.
UK’s Elevated Role
The UK's increased engagement, exemplified by the signing of the treaty and participation in large-scale military exercises like Talisman Sabre, positions it as a key strategic ally for Australia. The UK's Carrier Strike Group's presence in Darwin underscores this commitment and signals a broader Western effort to maintain a free and open Indo-Pacific.
Economic and Industrial Dimensions
Australia's substantial financial commitment supports not only submarine acquisition but also the expansion of US and UK submarine industrial bases. This investment aims to build domestic expertise and infrastructure, ensuring long-term operational capability.
Forecast
The treaty will likely accelerate UK-Australia defense integration, potentially mitigating risks from US policy shifts. However, the success of the AUKUS submarine program hinges on the US review outcome and the ability of Australia and the UK to manage complex technology transfers and industrial collaboration. Regional security will be closely tied to these developments, with China’s military posture remaining a central concern.
What the papers say
Gabriel Dominguez in The Japan Times reports that the Pentagon's policy chief Elbridge Colby confirmed Defense Secretary Pete Hegseth has ordered a department-wide review of the US-Australia nuclear submarine deal to assess its alignment with former President Trump's "America First" policy. Rod McGuirk of The Independent details the July 25 meeting in Sydney where Australia's Richard Marles and Britain's John Healey signed the 50-year treaty, emphasizing its historic significance and the inclusion of at least eight submarines, including second-hand US Virginia-class vessels. McGuirk also notes concerns about US submarine production delays and the cautious stance of Australian and British officials regarding the US review.
Ben Doherty in The Guardian highlights that the US is not a party to the new bilateral treaty signed by Australia and the UK, which was announced following the annual Aukmin talks. SBS provides a comprehensive overview, quoting UK Defence Secretary Healey calling the treaty a confirmation of AUKUS commitment for the next half-century and noting Australia's $368 billion investment. SBS also underscores the UK's growing strategic role, with the HMS Prince of Wales participating in the Talisman Sabre exercises, signaling a strong Western presence in the Indo-Pacific.
The South China Morning Post quotes Australian Prime Minister Anthony Albanese confirming Australia's payments to the US and reiterating confidence in the AUKUS pact despite the US review. The report contextualizes the deal as Australia's largest-ever defense expenditure aimed at countering China's ambitions. Bloomberg's article, while focused on Australia-India trade talks, indirectly reflects the broader regional strategic environment influencing Australia's defense posture.
Together, these sources illustrate a complex trilateral relationship under strain from US policy shifts, with Australia and the UK proactively reinforcing their alliance to ensure continuity in regional security and submarine capabilities.
How we got here
The AUKUS pact, announced in 2021, aims to counter China's growing military presence in the Indo-Pacific by providing Australia with nuclear-powered submarines. Australia committed up to A$368 billion over three decades, including payments to the US to expand submarine shipyards. The US review, initiated under former President Trump, questions the deal's alignment with US priorities, while Australia and the UK strengthen their bilateral ties through this treaty.
Go deeper
- What are the implications of the US review on the AUKUS submarine deal?
- How will the UK and Australia cooperate on submarine development without the US?
- What does this treaty mean for regional security in the Indo-Pacific?
Common question
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What Does the New Australia-UK Defence Treaty Include?
Australia and the UK have recently signed a landmark defence treaty, signaling a deepening of their military partnership. This agreement aims to bolster regional security and long-term cooperation, but what exactly does it entail? Many are wondering about the specifics of this treaty, why it was formed, and what it means for the Indo-Pacific region. Below, we explore the key details and answer common questions about this significant development.
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What Does the UK-Australia Defence Pact Mean for Regional Security?
The UK and Australia have recently signed a 50-year defence treaty to strengthen their military cooperation in the Indo-Pacific. This move raises questions about regional stability, the role of the US, and the future of global alliances. Below, we explore the key points of this historic agreement and what it could mean for the security landscape in the coming decades.
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What Are the Biggest Security Threats in 2025?
As global tensions rise in 2025, understanding the key security threats is more important than ever. From political conflicts to technological vulnerabilities, this year has seen significant challenges that impact nations worldwide. Below, we explore the main threats shaping the security landscape today and what they mean for the future.
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What’s Next for Military Alliances After AUKUS?
The recent signing of a 50-year defence pact between the UK and Australia marks a significant shift in regional security strategies. As new alliances form and existing ones evolve, many are asking what the future holds for military cooperation worldwide. Will these long-term treaties lead to greater stability or spark new conflicts? Here’s what you need to know about the future of military alliances and what they mean for global peace and security.
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Australia, officially known as the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands.
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Donald John Trump is an American politician, media personality, and businessman who served as the 45th president of the United States from 2017 to 2021.
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The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom or Britain, is a sovereign country located off the northwestern coast of the European mainland.
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Richard Donald Marles (born 13 July 1967) is an Australian politician and lawyer serving as the 19th deputy prime minister of Australia and the minister for Defence since May 2022. He has been the deputy leader of the Labor Party since 2019, and has serve
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David Lindon Lammy PC FRSA is a British Labour Party politician serving as Member of Parliament for Tottenham since 2000, and has served as Shadow Secretary of State for Justice and Shadow Lord Chancellor in Keir Starmer's Shadow Cabinet since 2020.
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John Healey is a British Labour Party politician serving as Member of Parliament for Wentworth and Dearne, formerly Wentworth, since 1997 and Shadow Secretary of State for Defence since 2020.
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Elbridge Andrew Colby (born December 30, 1979) is an American national security policy professional who is currently the under secretary of defense for policy. He previously served as deputy assistant secretary of defense for strategy and force developmen
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The United States of America, commonly known as the United States or America, is a country mostly located in central North America, between Canada and Mexico.
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AUKUS is a trilateral security pact between Australia, the United Kingdom and the United States, announced on 15 September 2021 for the Indo-Pacific region. Under the pact, the US and the UK will help Australia to acquire nuclear-powered submarines.