South Korean President Yoon Suk Yeol on Friday called for Japan to conduct a scientific analysis before releasing treated radioactive water into the sea from the crippled Fukushima nuclear power plant, Japanese lawmakers said.

With concern lingering about the impact of the treated water on the ocean environment, Yoon's remarks came during a meeting with former Japanese Prime Minister Yoshihide Suga, the soon-to-be new head of a cross-party group of lawmakers promoting friendly ties between Tokyo and Seoul.

South Korean President Yoon Suk Yeol (2nd from front L) meets with former Japanese Prime Minister Yoshihide Suga (3rd from front R) and others at a hotel in Tokyo on March 17, 2023. (Photo courtesy of secretariat of a cross-party lawmakers group promoting Japan-South Korea ties)(Kyodo)

Suga was quoted by lawmakers as telling Yoon, who became the first South Korean president to visit Japan in four years on Thursday, that the government has "proceeded with the plan" to discharge the treated water in conjunction with the International Atomic Energy Agency.

Regarding the treated water, the IAEA has carried out several safety reviews of the release plan to ensure the discharge is in line with international safety standards and poses no harm to public health and the environment.

In addition to South Korea, however, Japan's neighbors, China and Taiwan, have expressed opposition to Tokyo's decision, claiming the treated water would hurt the marine environment, food safety and human health.

In 2021, the government under Suga decided to release the treated radioactive water that is accumulating at the Fukushima Daiichi nuclear power plant, damaged by the devastating March 2011 earthquake and ensuing tsunami.

Yoon and Suga held talks a day after the president and Japanese Prime Minister Fumio Kishida agreed to work together to normalize relations by resolving major disputes.

Suga said he evaluates the outcome of the summit highly, voicing eagerness to take measures to boost person-to-person exchanges between Japan and South Korea, while Yoon responded by saying the leaders made "big progress" on bilateral ties.

At the summit, Yoon and Kishida confirmed their countries will restart reciprocal leader visits after a 12-year hiatus and bolster security cooperation.

Suga, a lawmaker of the ruling Liberal Democratic Party, will be the first former prime minister to take the South Korea outreach position since Yoshiro Mori held it between 2001 and 2010. He will replace former Finance Minister Fukushiro Nukaga as early as this month.

After serving as chief Cabinet secretary from 2012, Suga was premier from 2020 to 2021. He was involved in the negotiations leading to the 2015 agreement with South Korea to settle the issue of "comfort women" who were forced to work in Japanese wartime military brothels.

Relations between Tokyo and Seoul plunged to the lowest point in decades over a wartime labor row under Yoon's predecessor Moon Jae In after South Korea's top court in 2018 ordered two Japanese companies to compensate the plaintiffs.

But Yoon, who became president in May 2022, has been making efforts to improve ties with Japan while strengthening military cooperation with the United States as North Korean missile launches continue to threaten regional security.

On March 6, South Korea announced its solution to the wartime labor dispute, which centers on a government-backed foundation paying compensation to former Korean laborers and their relatives on behalf of the two Japanese firms.

As Kishida, who took office in October 2021, has been also willing to normalize communication with South Korea, former Japanese Prime Minister Taro Aso visited Seoul and held talks with Yoon in November last year. Yoon and Aso met again on Friday.

Separately, Yoon on Friday vowed to boost economic cooperation between Japan and South Korea at a meeting held in Tokyo by the major business lobby groups of both countries, a day after their announcement that they will each establish a foundation to tackle common issues.

"We will do our utmost to support (companies) so they can create innovative business opportunities," Yoon said, adding there are many areas over which the business communities in both countries could collaborate, including semiconductor production.

The Japan Business Federation and the Federation of Korean Industries said Thursday that the "future partnership" foundations will aim to conduct research and undertake projects in areas such as energy security and decarbonization, alongside looking at how to deal with aging societies and shared geopolitical risks.

The two business lobbies will each contribute 100 million yen ($750,000) to their respective foundations and plan to solicit funding from private companies in the future.

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