Russia has joined China's restrictive measures imposed on imports of fish and seafood from Japan following the release of treated radioactive water from the Fukushima plant, Russia's agricultural watchdog Rosselkhoznadzor said on Monday.

Japan started releasing water from the Fukushima nuclear power plant into the Pacific Ocean in August and was heavily criticized by China, which immediately banned all seafood imports from Japan.

Russia said the restrictions were imposed as a "precautionary measure" and will remain in place until comprehensive information is provided showing if the seafood is safe.

From January to September 2023, imports of fish and seafood from Japan to Russia totaled 118 tons, Rosselkhoznadzor reported.

China in late August banned all Japanese seafood imports over what it termed the "selfish" and "irresponsible" release of Fukushima wastewater.

Japan on Aug. 24 began the first discharge phase of treated water from the stricken plant into the Pacific Ocean in an operation it insists is safe. It began the second phase on Oct. 5.

But the move has sparked a fierce backlash from neighbors, led by the Chinese, who imported more than $500 million worth of seafood from Japan last year, according to customs data.

In 2011, three reactors at the Fukushima-Daiichi facility in northeastern Japan went into meltdown following a massive earthquake and tsunami that killed around 18,000 people.

The release of the wastewater has been deemed safe by the International Atomic Energy Agency (IAEA).

But Beijing says Tokyo has not proved the authenticity and accuracy of the nuclear wastewater data, nor that the ocean discharge of the water is harmless to the marine environment and human health.

In all, Tokyo intends to discharge into the Pacific Ocean around 540 Olympic swimming pools' worth of heavy water – some 1.3 million cubic meters (mcm) – from Fukushima in a gradual process lasting into the 2050s, according to the official schedule.

The water has been treated to remove radioactive substances with the exception of tritium, then diluted with seawater prior to discharge to ensure its radioactivity level does not surpass 1,500 becquerels per liter – 40 times less than the Japanese norm for this kind of operation.