Water containing radioactive tritium being pumped into Pacific via tunnel from Tepco plant, amid protests from China, South Korea and fishing communities

Japan has begun discharging more than 1m tonnes of tainted water into the Pacific Ocean from the wrecked Fukushima Daiichi nuclear power plant in a move that has prompted China to announce an immediate blanket ban on all seafood imports from Japan and sparked anger in nearby fishing communities.

The plant’s operator, Tokyo Electric Power (Tepco), pumped a small quantity of water from the plant on Thursday, two days after the plan was approved by Japan’s government.

Release plans approved by UN nuclear authority have caused outcry in China and concern for the reputation of Japan’s seafood

Japan is to begin releasing wastewater from the wrecked Fukushima Daiichi nuclear power plant from Thursday, in defiance of opposition from fishing communities, China and some scientists.

The prime minister, Fumio Kishida, said on Tuesday he had asked the plant’s operator, Tokyo Electric Power (Tepco), “to swiftly prepare for the water discharge” in accordance with plans approved by nuclear regulators, adding that the release would begin on Thursday, “weather and ocean conditions permitting”.

Authorities to begin release of a million tonnes of water from stricken nuclear plant after treatment to remove most radioactive material

The controversial release of more than a million tonnes of water from the wrecked Fukushima Daiichi nuclear plant will begin in the northern spring or summer, Japan’s government has said – a move that has sparked anger among local fishing communities and countries in the region.

The decision comes more than two years after the government approved the release of the water, which will be treated to remove most radioactive materials but will still contain tritium, a naturally occurring radioactive form of hydrogen that is technically difficult to separate from water.