Promoting Investable Nuclear Energy: The UK’s Accession to the CSC

On Friday 3 October 2025, the UK Government confirmed that the UK has deposited its instrument of accession to the Convention on Supplementary Compensation for Nuclear Damage (“CSC”) with the International Atomic Energy Agency. The UK will become the 12th Contracting Party to the CSC when it comes into force on 1 January 2026. 

As the first Contracting Party to the Revised Paris Convention and the Revised Brussels Convention to accede to the CSC, this will be an exciting milestone for the UK as it embraces the ‘Golden Age of Nuclear’. 

Schedule 22 to the Energy Act 2023 amends the Nuclear Installations Act 1965 and contains the necessary provisions to implement the CSC into UK law. Further technical changes required to implement the CSC into domestic law are contained within the draft Nuclear Installations (Compensation for Nuclear Damage) (Amendment) Regulations 2025.

Accession to the CSC will strengthen the UK’s nuclear third-party liability regime by ensuring that greater amounts of compensation are available to victims covered by the CSC in the event of a nuclear incident. In addition, it will provide the UK with treaty relations with key nuclear partners, including the US, Canada and Japan, which will reduce the risk of third party claims for nuclear damage being brought in these countries outside the nuclear liability regime and in turn remove some of the barriers to investment in the UK nuclear industry. 

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This article was written by Laura Tobin.