Australia and the United Kingdom have committed to enhancing their cooperation in advancing the development of the SSN-AUKUS submarines through the Nuclear-Powered Submarine Partnership and Collaboration Treaty.
Australian Minister for Defence Richard Marles and British Secretary of State for Defence John Healey formalized the bilateral agreement during the U.K.-Australia Defence Ministers’ Meeting held in Geelong on Saturday.
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According to the U.K. Ministry of Defence, the Geelong Treaty, along with the trilateral AUKUS Naval Nuclear Propulsion Agreement, will provide both nations with innovative undersea capabilities to support stability in the Indo-Pacific and Euro-Atlantic regions.
The agreement aims to enhance collaboration between Australia and the U.K. in the design, construction, operation, maintenance and eventual disposal of the SSN-AUKUS submarines. It also addresses the development of the necessary infrastructure, regulatory systems and workforce to support Australia’s SSN-AUKUS program.
The Geelong Treaty aligns with the objectives of the AUKUS trilateral security partnership between Australia, the United Kingdom and the United States, particularly with the U.K.-Australian bilateral defense cooperation under Pillar 1.
In a statement issued before the deal’s signing, the ministers noted that the treaty would also promote job creation, stimulate economic growth, and strengthen the submarine industrial bases of Australia and the United Kingdom.

