The head of the UN's nuclear watchdog will deliver a comprehensive safety review on Japan's controversial plan to release huge amounts of treated and diluted nuclear wastewater from the crippled Fukushima plant, reported German news agency (dpa).

Rafael Grossi, director-general of the International Atomic Energy Agency (IAEA), is set to hand over the report to Japanese Prime Minister Fumio Kishida tomorrow.

During his four-day visit, Grossi will also travel to the Fukushima Daiichi plant and inaugurate an...