Japan's environment minister called Tuesday for water contaminated with low-toxicity radioactive tritium at the crippled Fukushima nuclear plant to be discharged into the Pacific Ocean, potentially provoking controversy with South Korea that has expressed concerns about the idea.

"Although I'm not the minister in charge, I believe there's no choice but to dump the water (into the ocean) and dilute it," Environment Minister Yoshiaki Harada told a press conference, a day before Prime Minister Shinzo Abe's planned Cabinet reshuffle.

Even after being treated, the water, used to cool reactor cores that suffered meltdowns at the plant following the 2011 earthquake and tsunami, remains contaminated with tritium.

But the water, currently stored in tanks at the Fukushima plant, is regarded by the government as relatively harmless to humans.

Seoul has expressed concern over the possibility that the water could be discharged into the ocean. Local fishermen are also opposed to the release of the water into the sea, fearing the potential impact on fish stocks.

The Japanese government has yet to decide on how to dispose of the accumulating water. The tanks storing the water are expected to be full by the summer of 2022, according to Tokyo Electric Power Company Holdings Inc., the operator of the Fukushima plant.

A nuclear expert from the International Atomic Energy Agency said in 2018 that a controlled discharge of such contaminated water "is something which is applied in many nuclear facilities, so it is not something that is new."

Harada said his view was based on a visit to the Fukushima complex, where he saw a number of tanks storing the water, and the Nuclear Regulation Authority's support for the water discharge.

In an apparent reference to South Korea, Harada added the most important thing for Japan is to "provide sincere explanations" to countries that may oppose Tokyo's policy.

The environment minister made the remarks as he looked back on his time in the post since October last year.

In August, a government panel began discussing the possibility of long-term water storage. It has looked at other options such as discharging it into the sea and vaporization.

Toxic water produced by cooling debris and other processes at the Fukushima plant is purified using the Advanced Liquid Processing System, said to be capable of removing almost all radioactive materials except tritium.

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