SSN-AUKUS

SSN-AUKUS is the designation for a new class of conventionally-armed, nuclear-powered attack submarine (SSN) that the United Kingdom and Australia will construct as the centerpiece of "Pillar 1" of the AUKUS security partnership. The design was announced on 13 March 2023 at a trilateral leaders' summit in San Diego, where US President Joe Biden, UK Prime Minister Rishi Sunak, and Australian Prime Minister Anthony Albanese unveiled the "optimal pathway" for delivering nuclear-powered submarines to Australia.

The boat is based on the UK's next-generation SSN(R) replacement programme for the Astute class, but will integrate US technologies including the common vertical launch system and combat systems derived from the Virginia-class. It will be powered by a UK-designed Rolls-Royce nuclear reactor using highly-enriched uranium fuel in a sealed "life-of-boat" reactor, meaning Australia will not need a domestic enrichment or reprocessing capability.

Under the announced timeline:

• The UK will receive its first SSN-AUKUS in the late 2030s, built at BAE Systems' Barrow-in-Furness shipyard.
• Australia will build its boats at the Osborne Naval Shipyard in South Australia, with the first Australian-built SSN-AUKUS expected in the early 2040s.
• As an interim measure, the US will sell Australia three Virginia-class submarines beginning in the early 2030s, with an option for two more.

SSN-AUKUS has drawn scrutiny on non-proliferation grounds because it involves the transfer of naval nuclear propulsion technology and highly-enriched uranium to a non-nuclear-weapon state party to the NPT. Australia, the UK, US, and IAEA have been negotiating safeguards arrangements under Article 14 of Australia's comprehensive safeguards agreement. Critics, including China and some NPT states parties, argue it sets a precedent; proponents note Australia's strong non-proliferation record and that the reactors are sealed units never opened on Australian soil.