Masahiro Kikuchi

On 15 September 2021, Australia, the United Kingdom and the United States of America announced the creation of an enhanced trilateral security partnership agreement called “AUKUS” aimed at deepening diplomatic ties, security, and defense cooperation in the Indo-Pacific region. In connection with this, the United Kingdom and the United States have agreed to support Australia’s acquisition of at least eight conventionally armed, attack type nuclear-powered submarines. On 22 November, the three states signed the Exchange of Naval Nuclear Propulsion Information Agreement, which will provide a mechanism to access the training and education necessary for learning how to build, operate and support nuclear-powered submarines. Australia broke off a purchase contract it had signed with France in 2016 to obtain normal-type submarines and instead made the choice to acquire nuclear-powered submarines.

The NPT prohibits each non-nuclear-weapon State Party to the Treaty (NNWS) to manufacture or otherwise acquire nuclear weapons or other nuclear explosive devices; and each nuclear-weapon State Party to the Treaty (NWS) to transfer and to assist to NNWS to manufacture and acquire the nuclear weapons or other nuclear explosive devices. However, the NPT excludes nuclear-powered military ships such as nuclear-powered submarines from the targets of its prohibition. The Comprehensive Safeguards Agreement (CSA) of the International Atomic Energy Agency (IAEA), which conducts verification under the NPT, has also excluded nuclear materials in a non-proscribed military activity—such as nuclear fuels in nuclear-powered submarines—from its safeguards application in Article 14. At the time of the CSA’s establishment in 1970, there were already concerns about proliferation scenarios involving production of nuclear weapons or other nuclear explosive devices via nuclear material for non-proscribed military activities. However, for the reasons that (1) attempts to verify nuclear fuel might conflict with classified military information and (2) there was, at the time, no NNWS which possessed a nuclear-powered submarine, the Article 14 of the CSA was agreed that the IAEA and the State which requires no application of safeguards to a non-proscribed military activities should make an Arrangement which shall identify the period or circumstance during which safeguards will not be applied, but that in any event, safeguards provided for in the CSA shall again apply as soon as the nuclear material is reintroduced into a peaceful nuclear activity.

To this point, no state has yet invoked the provisions of Article 14 of the CSA, but there were cases in which Canada and Brazil explored the possibility of applying Article 14 to their non-proscribed military activities. In the late 1980s, Canada approached the IAEA to ask for an exemption from Article 14 with the hope of making arrangements to export its uranium to an NWS for enrichment and processing so that it could be reimported as fuel for Canadian nuclear submarines. The IAEA and Canada discussed the point at which the nuclear material would be withdrawn from safeguards. However—regarding the timing of the exemption—the IAEA was unable to reconcile Canada’s argument that the exemption should be granted when the nuclear material to be exported exists in within its own borders with the IAEA’s argument that it should be granted shall at the time of transfer out of Canada due to discrepancy in Canada’s inventory level, and the talks were suspended with no arrangement concluded. On the other hand, Brazil—which has explored the possibility of obtaining nuclear-powered submarines—has been developing a land-based prototype reactor under IAEA safeguards, but the project has been confronted with numerous delays in the domestic fuel cycle for conversion, enrichment, and fabrication of fuel elements to be used with the submarine. As such, Brazil has not yet approached the IAEA to initiate the discussion on invoking the non-application of safeguards to nuclear material for use in a non-proscribed military activity.

If Australia proceeds with its goal of acquiring nuclear-powered submarines, the proliferation risks—such as nuclear material diversion from naval fuel programs which are not subject to the IAEA safeguards by the application of the Article 14 of the CSA—must be considered. Generally, a small-size reactor which is loaded in submarines uses high enriched uranium (HEU) for convenience of efficiency of power generation and the ability to operate for long stretches at a time without refueling. Australia needs to construct a uranium enrichment facility to supply the necessary amount of HEU to eight nuclear-powered submarines under stable conditions. Currently, Australia does not have such a uranium enriched facility. Several uranium enrichment plants have been already constructed and operated as commercial facilities in several NNWSs. The uranium enrichment technologies employed here are fundamentally similar to those at a facility which produces HEU for fuels in nuclear-powered submarines. Their differences lie in the fact that uranium enrichment levels vary depending the intended purpose, as well as the presence of the IAEA safeguards, which apply to HEU produced in uranium enrichment facilities in NNWSs. If Australia does not have its own peaceful nuclear fuel cycle including plans of electric power generation and instead constructs a uranium enrichment facility for the purpose of producing HEU to be used in nuclear-powered submarines, the HEU produced in the facility will not be subject to the IAEA safeguards according to Article 14 of the CSA.

If Australia and the IAEA were to reach an agreement that excludes nuclear materials used in nuclear submarines from the verification safeguards, this could set a precedent by which other NNWSs possessing uranium enrichment facilities might seek to obtain nuclear-powered combat vessels—including submarines—and to pursue new military uses of nuclear weapons for purposes other than the nuclear weapons prohibited by the NPT. Worse still, this could potentially open a loophole in CSA that could be exploited by NNWSs to divert nuclear materials to be used in the development of nuclear bombs.

The IAEA secretariat stated that it is ready to discuss possible safeguards implementation with the AUKUS parties within the existing legal framework, and has demanded that said parties fulfill their reporting obligation under the respective safeguards agreements and additional protocols. Further developments arising from these discussions will be monitored with great interest.

Masahiro Kikuchi: Former Board Member, Nuclear Material Control Center