This aerial view shows the tanks containing treated radioactive wastewater at the Fukushima Daiichi nuclear power plant in Fukushima, northern Japan, on Aug  22, 2023. (PHOTO / AP)

BEIJING - China strongly condemns the Japanese government for disregarding international opposition and starting to discharge the nuclear-contaminated water from the tsunami-wrecked Fukushima Daiichi nuclear power plant on Thursday.

China has made serious demarches to Japan and asked it to stop the discharge, a Foreign Ministry spokesperson said in a statement, adding that Japan "is bound to face international condemnation for many years to come".

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The Fukushima nuclear accident, which took place 12 years ago, has already caused the leakage of large amounts of radioactive substances into the ocean, and Japan should avoid dumping nuclear-contaminated water, which could cause "a man-made secondary disaster", the spokesperson said.

The Japanese government failed to clarify a series of doubts about its ocean discharge decision, including proof that the ocean discharge is safe and harmless to marine environment and people’s health, the spokesperson pointed out

The Japanese government failed to clarify a series of doubts about its ocean discharge decision, including proof that the ocean discharge is safe and harmless to marine environment and people’s health, the spokesperson pointed out.

Also, Japan failed to have thorough consultations with other stakeholders about the ocean discharge, the spokesperson said.

"By dumping the water into the ocean, Japan... has turned itself into a saboteur of the ecological system and polluter of the global marine environment," the spokesperson said.

Also on Thursday, an official with the Ministry of Ecology and Environment (National Nuclear Safety Administration) said Japan's decision has put its own interests above the well-being of humanity, which is "extremely selfish and irresponsible".

Members of the Hong Kong Federation of Fujian Associations hold a protest outside the Consulate-General of Japan in Hong Kong on Aug 23, 2023 in response to Japan's decision to release wastewater from its Fukushima nuclear power plant into the Pacific Ocean from Aug 24. (CALVIN NG / CHINA DAILY)

"We urge the Japanese side to heed the voice of the international community, conduct the disposal of the nuclear-contaminated water in a scientific, safe and transparent manner, and accept strict international supervision," the official said in a statement in response to a media query.

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China will strengthen radiation monitoring in sea areas under its jurisdiction this year to track and evaluate the possible impact of Japan's discharge to safeguard its national interests and people's health, the official said.

With Xinhua inputs