People rally to protest against Japan's planned discharge of radioactive wastewater into the Pacific Ocean in Seoul, South Korea, May 20, 2023. (PHOTO / XINHUA)

SEOUL - Tens of thousands of South Koreans gathered in central Seoul on Saturday to voice their opposition to Japan's planned discharge of radioactive wastewater from its crippled Fukushima Daiichi nuclear power plant into the Pacific Ocean.

"Stop Japan's dumping of nuclear contaminated water into ocean. Oppose the dumping from Fukushima," protesters shouted in unison with civic activists and politicians joining the rally.

Lee Jae-myung, chairman of the main liberal opposition Democratic Party, told the protesters that the South Korean government should not agree with Japan, which would "throw away" the contaminated water regardless of whether the neighboring countries would suffer the damage or the wastewater would contaminate oceans around the world

Lee Jae-myung, chairman of the main liberal opposition Democratic Party, told the protesters that the South Korean government should not agree with Japan, which would "throw away" the contaminated water regardless of whether the neighboring countries would suffer the damage or the wastewater would contaminate oceans around the world.

Lee said earlier this week that Japan should reuse the water from the Fukushima power plant as drinking water if Japan's claims are true that the contaminated water is safe enough to drink after being treated.

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The protesters also criticized the South Korean government's plan to dispatch a 21-member team of experts to Japan in a bid to review the contaminated water discharge process for six days from Sunday.

Kang Eun-mi of the minor progressive Justice Party said it will be a "secret" briefing session provided by the Japanese side as private experts were excluded from the team, of which the list was undisclosed.

The lawmaker noted that the team will not be allowed to collect even a drop of the contaminated water as a sample, while South Korean reporters were not allowed to accompany the team.

"Anxiety and concern of our people are put on the back burner. It shows a terrible aspect of humiliating diplomacy, where (South Korea) accepts Japan's closed-door briefing gratefully," Kang said.

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Despite grave concerns expressed by Japan's neighbors and the Pacific island countries, the Japanese government has decided to release radioactive wastewater from the crippled nuclear power plant in Fukushima into the Pacific Ocean "in spring or summer."