TOKYO (Kyodo) -- China on Thursday collected Japanese fish samples for the first time as part of U.N. nuclear watchdog-led additional monitoring of the discharge of treated radioactive water from the wrecked Fukushima power plant into the sea.

Based on an agreement between the Japanese and Chinese governments in September to work toward lifting an import ban on Japanese seafood products, concentration levels of radioactive materials in the samples will be analyzed at labs.

"I'm very happy that we have been able to come up with the creative solution that allows countries that have concerns to take a more active role in the process, get more confidence and more trust in what is being done," International Atomic Energy Agency chief Rafael Grossi said at a press conference in Tokyo.

Chinese Foreign Ministry spokesman Guo Jiakun said Wednesday that Beijing hopes the IAEA will continue to play a constructive role, implement long-term, independent and strict monitoring of the discharge, and safeguard the marine ecology and human health.

China imposed the blanket ban immediately after the treated water discharge began in August 2023.

Tokyo and Beijing subsequently agreed to conduct additional monitoring of the water release involving other stakeholders including China within the IAEA system. This prompted Beijing to begin arrangements for lifting the ban.

Earlier in the day, Grossi met with Prime Minister Shigeru Ishiba, who expressed his gratitude for the IAEA's support in Fukushima's reconstruction, including decommissioning of the Fukushima Daiichi reactors and the discharge of treated water.

International scientists and IAEA experts selected flounder caught off the coast of Fukushima Prefecture the same day as marine biological samples for testing and analysis.

The fish will be provided to China and other participating countries after being processed at a research institute in Chiba Prefecture near Tokyo.

During his three-day trip to Japan through Thursday, Grossi joined the scientists and IAEA experts in seawater sampling near the Fukushima plant on Wednesday.

On Friday, the scientists are expected to take samples of treated water in a tank before it is diluted with seawater for the first time as part of the second additional monitoring mission. The latest mission comprises China, France, South Korea and Switzerland, according to the government.

The first IAEA-led additional monitoring with international scientists was conducted last October. Beijing later announced it found no abnormalities in seawater samples collected near the Fukushima plant, damaged in the wake of the 2011 earthquake and tsunami disaster.

The radioactive water is processed through an advanced liquid processing system, or ALPS, to remove most contaminants, except for the relatively nontoxic tritium, and diluted with seawater to one-40th of the concentration permitted under Japanese safety standards before it is released into the Pacific Ocean.