UK: ONR publishes report on international collaboration for small modular reactors

The Office for Nuclear Regulation (ONR) has published a report on international regulatory collaboration for small modular reactors (SMRs) and advanced modular reactors (AMRs). The report highlights how the UK regulator collaborates with international counterparts to develop more efficient, harmonised approaches to reactor design assessment, satisfying industrial needs and promoting nuclear safety worldwide. Among the key achievements presented in the report is the signing of a trilateral memorandum of cooperation with the US Nuclear Regulatory Commission (NRC) and Canadian Nuclear Safety Commission (CNSC) in 2024, which established a framework for streamlined regulation, and leading international harmonisation efforts through the ONR’s vice-chair role in the IAEA’s SMR Regulators’ Forum. The ONR also invited five European nuclear regulators to observe the Rolls-Royce assessment process, a pioneering step in international regulatory practices.
The report details several collaborative activities undertaken by the ONR between late 2024 and early 2025 to advance regulatory harmonisation, including workshops on key technical issues and high-level meetings with international partners and industry representatives. Tim Parkes, ONR’s Head of Regulation – GDA, said that the office’s efforts at international cooperation are delivering “tangible efficiency improvements” to the assessment of new reactor designs and the harmonisation of regulatory approaches to SMRs and AMRs. They will also support the deployment of standard designs and help ensure the highest safety standards at a global level.