AUKUS partners advance SSN and UUV programmes

A file image of the Virginia-class submarine USS Vermont, which underwent maintenance at HMAS Stirling in October-November 2025. (US Navy)

Australia, the UK, and the US have jointly announced plans to advance Pillar 1 and Pillar 2 initiatives under the AUKUS trilateral partnership. The announcements were made on the sidelines of the Shangri-La Dialogue in Singapore in late May.

Under Pillar 1, the partners confirmed final arrangements to operationalise the Submarine Rotational Force-West (SRF-West) from the end of 2027, supporting the delivery of three second-hand Virginia-class nuclear-powered submarines (SSNs) to Australia.

They also announced the first Pillar 2 project, aimed at developing “payloads and enabling systems” for unmanned underwater vehicles (UUVs), with initial deliveries from 2027.

SRF-West will establish a rotational presence of one UK Astute-class and up to four US Virginia-class SSNs at the Royal Australian Navy's (RAN's) HMAS Stirling base in Western Australia. Australia has earmarked AUD8 billion (USD5.7 billion) to upgrade infrastructure and logistics support at the facility.

The partners said SRF-West will expand logistics and maintenance infrastructure required for submarine deployments, enhancing Australia's ability to operate and sustain its future Virginia-class fleet. The US Navy (USN) will begin deploying personnel to HMAS Stirling from the second half of 2026 to support the initiative.

Australia's Department of Defence (DoD) has previously said the RAN is scheduled to receive its first Virginia-class SSN in the early 2030s.

Speaking on 31 May, Australia's Defence Minister Richard Marles said the decision to procure three second-hand Virginia-class submarines was driven by cost considerations and efforts to simplify RAN operations.