Tanks containing treated water at the crippled Fukushima nuclear power plant are likely to reach capacity around the fall of 2023, later than the initially predicted spring of next year, as the pace of the accumulation of radioactive water slowed in fiscal 2021.

The slowdown, based on an estimate by operator Tokyo Electric Power Company Holdings (Tepco), gives some breathing space to Prime Minister Fumio Kishida's government if any roadblocks are thrown up in the plan to discharge the treated water into the sea starting around spring next year.

China and South Korea, as well as local fishing communities that fear reputational damage to their products, remain concerned and have expressed opposition to the plan.