The Royal Navy confirmed the deployment of the nuclear-powered attack submarine HMS Anson to Australia, as part of the commitments assumed by the United Kingdom within the AUKUS strategic alliance. The Astute-class submarine departed from the Faslane base on January 10 and made an initial stop in Gibraltar before continuing its transit toward the Indo-Pacific.
According to what was officially announced in 2025, HMS Anson will join the Submarine Rotational Force–West (SRF-West) during 2026, based at HMAS Stirling near the city of Perth, in Western Australia. This is a significant deployment, given that the Royal Navy currently has limited availability of nuclear-powered attack submarines in active service.
Commitment to AUKUS
In December, UK Defence Secretary Luke Pollard confirmed that an Astute-class submarine would be assigned to SRF-West as part of the United Kingdom’s commitment to AUKUS. Referring to this decision, Pollard stated that the deployment constitutes “a central planning assumption for the Royal Navy under AUKUS” and affirmed that the government considers the commitment to be “realistic and manageable within existing force planning.”
The deployment of HMS Anson takes place in a context in which the United Kingdom seeks to reinforce its naval presence in the Indo-Pacific, in coordination with Australia and the United States, while the development of the future SSN-AUKUS nuclear submarine progresses.
Limited availability of nuclear attack submarines
The situation of the British submarine fleet is marked by operational constraints. According to official information and specialized reports, other Astute-class units are in various states of maintenance or low availability. HMS Astute is awaiting the completion of HMS Audacious’s maintenance period before entering a mid-life refit, while HMS Ambush is at a very low level of readiness. For its part, HMS Agamemnon, commissioned in September, is not yet operational.
In December, the First Sea Lord warned about the situation in the North Atlantic by stating: “I can also tell you today that the advantage we have enjoyed in the Atlantic since the end of the Second World War is at risk. We are holding on, but not for long.”
Recent precedents and allied cooperation
The deployment of HMS Anson adds to recent precedents that reflect the operational strain on the Royal Navy. In July 2025, the submarine’s return to the Clyde naval base in Scotland was confirmed, leaving the aircraft carrier strike group led by HMS Prince of Wales (R09) without submarine cover during its deployment to the Western Pacific. At that time, British naval sources indicated that no Royal Navy nuclear-powered attack submarines were at sea.
In this context, cooperation with allies has become increasingly important. Activities by U.S. Navy submarines have helped mitigate the temporary absence of British units, particularly in strategic areas such as the Greenland–Iceland–United Kingdom (GIUK) gap, which is key to North Atlantic security.
The SSN-AUKUS program and Australia’s role
The deployment of HMS Anson is directly linked to the development of the SSN-AUKUS program, which envisages the construction of new British-designed nuclear-powered attack submarines using technology contributed by Australia, the United Kingdom and the United States. In October 2023, BAE Systems confirmed the award of a USD 4.9 billion contract to advance the design and development phase of the program through 2028.
In parallel, in October 2025, U.S. President Donald Trump confirmed the sale of Virginia-class nuclear-powered attack submarines to the Royal Australian Navy. After meeting with Prime Minister Anthony Albanese, Trump stated that the program “is moving quickly and very well” and assured that “Australia will get the submarines,” reaffirming U.S. commitment to AUKUS.
As planned, Australia will acquire between three and five Virginia-class submarines as an interim solution, while developing the industrial infrastructure and operational experience required for the future entry into service of the SSN-AUKUS submarines, expected in the 2040s.
A key deployment in a transitional context
The duration of HMS Anson’s stay in Australia has not yet been officially specified. However, statements from U.S. officials indicate that rotations within SRF-West could last around six months, although for British units, which must cover distances of approximately 9,500 nautical miles, longer stays cannot be ruled out.
The deployment of HMS Anson reflects the balance currently faced by the Royal Navy between its international commitments in the Indo-Pacific and the limited availability of its nuclear submarine fleet, in a scenario marked by ongoing modernization and strategic cooperation with its allies.
Cover image obtained from Naval Outlook.
You may also like: British A400M aircraft from Malvinas makes a stopover at a Chilean Air Force Military Base
