China renewed its call on Tuesday for Japan to halt a planned discharge of treated radioactive water from the crippled Fukushima nuclear power plant into the Pacific Ocean, questioning Tokyo's claim that it is the safest and most reliable option.

The Chinese Foreign Ministry said a safety review of the plan presented the same day by the International Atomic Energy Agency "should not be the 'shield' or 'green light' for Japan's discharge of nuclear-contaminated water into the ocean," adding that the report "failed to fully reflect views from experts that participated in the review."

Chinese Foreign Ministry spokeswoman Mao Ning attends a press conference in Beijing on July 4, 2023. (Kyodo)

The IAEA concluded in its report that Japan's plan on the water release aligns with international safety standards and the move would have "a negligible radiological impact on people and the environment." The Japanese government aims to start the discharge around this summer.

Shortly before the IAEA released its safety review, ministry spokeswoman Mao Ning expressed doubt at a press conference that the report will serve as justification for Japan to move ahead with the controversial water release.

She noted that the U.N. nuclear watchdog conducted its assessment at the request of the Japanese government, and its mandate was limited to the ocean discharge option.

The ministry criticized Japan for adopting the ocean discharge plan "simply for saving cost" and taking the Pacific Ocean as the "sewer."

"No matter what the report says, it will not change the fact that Japan will release millions of tons of Fukushima nuclear-contaminated water into the Pacific Ocean in the next three decades," the statement said.

"If Japan insists on going ahead with the plan, it will have to bear all the consequences arising from this," the ministry added.

Beijing urged Tokyo to work with the IAEA to establish a long-term monitoring mechanism that would involve stakeholders including Japan's neighboring countries.

Earlier in the day, Chinese Ambassador to Japan Wu Jianghao stated in a news conference in Tokyo that the IAEA, which promotes the safe, secure, and peaceful use of nuclear technology, is "not an appropriate agency to assess the long-term impact of nuclear-contaminated water on the marine environment."

Massive amounts of radioactive water have been generated in the process of cooling melted reactor fuel at the Fukushima Daiichi nuclear power plant, which was hit by a major earthquake and tsunami disaster in 2011.

The water is treated at a processing facility to remove most contaminants, except tritium, and stored in tanks installed on the premises. But the tanks are nearing capacity.

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