China expressed Tuesday strong opposition to Japan's plan to release treated radioactive water from the crippled Fukushima nuclear power plant into the sea later this week, while South Korea said it has found no scientific or technical issues despite opposition among many locals.

The Hong Kong government said it will restrict Japanese seafood imports from 10 prefectures -- Tokyo, Fukushima, Chiba, Gunma, Tochigi, Ibaraki, Miyagi, Niigata, Nagano and Saitama -- beginning Thursday when the water discharge will start.

The government of Macao, another semiautonomous region, said it will ban imports of various food items, including seafood, vegetables, meat and fruit, from the 10 prefectures beginning Thursday.

China's Foreign Ministry spokesman Wang Wenbin speaks at a press conference in Beijing on Aug. 22, 2023. (Kyodo) ==Kyodo

Chinese Vice Foreign Minister Sun Weidong summoned Japan's Ambassador to China, Hideo Tarumi, and lodged a formal protest against the planned water release, expressing Beijing's grave concerns and strong opposition, according to the Chinese Foreign Ministry.

Sun warned that the country will "take necessary steps to protect the marine environment, food safety and people's health," suggesting it could implement additional measures to restrict Japanese seafood imports.

Beijing strongly urges Tokyo to "stop its wrongdoing" and "cancel the plan," Sun said.

Tarumi told Sun in response that it is "regrettable" that China makes claims that are "not based on science" but expressed Japan's readiness to keep communicating with the neighboring country even after the ocean discharge begins, according to the Japanese Embassy in Beijing.

Park Ku Yeon, the first deputy chief of South Korea's Office for Government Policy Coordination, said in a briefing that the government will maintain a vigilant watch over the process, stressing that it does not actively support Japan's course of action.

Should implementation of the water release plan deviate from what was conveyed to Seoul by Tokyo, the government will seek an immediate halt to the discharge, Park said, adding that it will do its best to minimize possible damage to the domestic fisheries industry and share monitoring data with the public.

The response comes as South Korea said last month it respected the outcome of the International Atomic Energy Agency's safety review on Japan's plan to release the processed water that has been accumulating at the Fukushima Daiichi plant, which was hit by an earthquake and ensuing tsunami in 2011.

But South Korea's main opposition Democratic Party on Tuesday held a protest against the decision, criticizing the government's assertion that Japan's water release plan poses no scientific or technical issues.

People protest in front of the Japanese Embassy in Seoul on Aug. 22, 2023, against Japan's decision to release treated radioactive water from the crippled Fukushima Daiichi nuclear power plant into the sea on Aug. 24. (Kyodo) ==Kyodo

"Once contaminated water is dumped into the ocean, that can never be undone. The resulting harm to our oceans and future generations will endure permanently. It must be stopped," the party's leader Lee Jae Myung said.

Several civic groups across the country also held protests against the water release, according to local media reports.

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