Trilateral statement on the commencement of the Submarine Tendered Maintenance Period.


The Honourable Richard Marles MP, Deputy Prime Minister and Minister for Defence, Australia; the Right Honourable John Healey MP, Secretary of State for Defence, United Kingdom; and the Honorable Lloyd J. Austin III, Secretary of Defense, United States.

Today, AUKUS nations will commence the Submarine Tendered Maintenance Period (STMP) at HMAS Stirling in Western Australia. This is a historic milestone for the AUKUS partnership, which promotes stability and security in the Indo-Pacific region and beyond.

Over the last year, Australian personnel have undergone training provided by the U.S. and the UK to understand how to safely operate, maintain and regulate Australia’s future conventionally-armed, nuclear-powered submarine (SSN) capability, to be delivered under AUKUS.

Continuing this training, the STMP is a significant step in Australia’s acquisition of SSNs, marking the first time Australian personnel will directly participate in the maintenance of a nuclear-powered submarine in Australia. Building on the success of earlier U.S. SSN visits, Australian personnel will undertake hands-on learning and observe a range of activities during the STMP.

Through this activity, uniformed and civilian personnel from our three nations will work together to transfer knowledge and skills necessary to set us on the trajectory to establish Submarine Rotational Force – West (SRF-West) and accelerate Australia’s efforts to be ‘sovereign ready’ to own and operate its own sovereign SSN capability. SRF-West will involve the rotational presence of one UK Astute class and up to four U.S. Virginia class submarines at HMAS Stirling.

Australians are now learning, and serving, alongside their shipmates in both the Royal Navy and United States Navy’s submarine forces, in their training establishments, gaining the knowledge and experience needed to support and operate future Royal Australian Navy SSNs.

Nuclear stewardship is an absolute priority for AUKUS partners. During the STMP, simulated training exercises will help Australia increase its knowledge and implement a safety culture that ensures the highest level of protection to our people, the public and the environment.

AUKUS partners are also committed to setting the highest nuclear non-proliferation standard for the acquisition of a conventionally-armed, nuclear-powered submarine capability for Australia.

Our navies are committed to reinforcing the same guiding principles within Australia that have allowed the United States and United Kingdom to safely operate nuclear-powered ships for nearly 70 years. We are stronger, safer and more effective when we learn, train, work and operate together. The STMP, coupled with the continued learning across our three nations, is an opportunity to share critical skills, training and knowledge and further improve our interoperability.

The STMP is a foundational activity under the AUKUS partnership that will strengthen our defence capabilities, better deter aggression in the region and uphold the rules-based international order.

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Published 23 August 2024