Japan has begun considering a rescue plan for its domestic fisheries after China reacted to the discharge of treated radioactive water from the crippled Fukushima nuclear power by imposing a blanket import ban on Japanese fishery products, officials said Friday.

The government seeks to mitigate the Chinese move's negative impact on the fishery industry while continuing to urge China to lift the measure it deems "not based on science."

Japan's seafood exports to China stood at around 160 billion yen ($1 billion) in 2022, some 40 percent of total outbound shipments in value terms, according to government data.

A fisherman maintains fishing gear at a port in Soma in Fukushima Prefecture, northeastern Japan, on Aug. 24, 2023, as Japan begins releasing treated radioactive water from the crippled Fukushima nuclear power plant, located in the vicinity, into the sea. (Kyodo) ==Kyodo

China further tightened the screw on Friday by banning food production operators from purchasing or using seafood originating in Japan to process it for sale.

"The potential impact felt by those who have been exporting (to China) will be severe. We must seriously consider what we can do to rescue them," Finance Minister Shunichi Suzuki said at a press conference.

Relevant ministries in charge of fisheries and trade are expected to work out details, including the most suitable forms of assistance.

China's outright ban on Japanese seafood comes amid expectations for a thaw in bilateral ties that have been cooled in recent years. The two nations are at odds over the sovereignty of uninhabited islets controlled by Japan and claimed by China, among other contentious issues.

Japan on Thursday began releasing treated radioactive water from the Fukushima Daiichi nuclear power plant into the Pacific Ocean, a critical step toward decommissioning of the facility wrecked by the 2011 earthquake and tsunami. Most radionuclides, except for tritium, are removed from the water before it is discharged.

The water release plan has met strong opposition from Japan's neighbors. A day after the first discharge, plant operator Tokyo Electric Power Company Holdings Inc. said it had found no traceable tritium in seawater samples near the complex.

Nonetheless, worries persist about the added reputational harm to local fishermen and the seafood industry.

Japan has allocated 80 billion yen to cope with such damage and help fishermen to carry on with their business. However, the funds are not destined for those in the seafood processing industry.

TEPCO President Tomoaki Kobayakawa said in a meeting Friday with Economy, Trade and Industry Minister Yasutoshi Nishimura that his company is ready to provide appropriate support to businesses affected by China's response.

A shopper looks at eels from Japan at a supermarket in Hong Kong on Aug. 18, 2023. (Kyodo) ==Kyodo

Research firm Teikoku Databank estimates that 727 Japanese firms in the food industry that export seafood products to China either directly or indirectly will be impacted by the latest ban.

On average, more than half of total sales came from China-bound exports for the surveyed companies, and 164 are mainly engaged in seafood processing or sales.

Tritium is known to be less harmful to human health than other radioactive materials such as cesium and strontium as it emits very weak radiation and does not accumulate in the body, experts say.

Nuclear power plants worldwide routinely release treated water containing low concentrations of tritium and other radionuclides into the environment as part of normal operations, according to the International Atomic Energy Agency.

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