The World Trade Organization on Thursday ruled in favor of a South Korean ban on imports of some Japanese fishery products introduced in the wake of the 2011 Fukushima nuclear disaster, reversing an earlier decision against the restrictions.

The decision, delivered by the WTO’s appellate body for dispute settlements, the highest judicial entity of the organization’s mechanism to resolve disputes, leaves Japan with no legal recourse in a battle that has dragged on for years.

The appellate body invalidated the conclusions of a dispute settlement panel that made the earlier decision because, it said, the panel “erred in its interpretation and application” of WTO rules on food safety.

The appellate body, however, did not look at the details of the amount of contaminants in Japanese food products or how much protection South Korean consumers should have.

Farm minister Takamori Yoshikawa on Friday reiterated that Japanese food products are safe. “I find (the WTO decision) regrettable when I think about recovery efforts made by those affected by the disaster,” he told a news conference.

Foreign Minister Taro Kono told South Korean Ambassador Lee Su-hoon on Friday that Tokyo will continue to push for the measures to be scrapped in bilateral talks.

The South Korean government welcomed the decision Friday, saying it will maintain the current import ban on fishery products from Fukushima Prefecture and surrounding areas.

The ban will remain in place unless it is officially proven that there is no problem with importing fishery products from the areas concerned, Yoon Chang-ryeol, head of the Office for Government Policy Coordination, said during a press briefing.

The situation will continue to weigh on Japan, which aims to achieve the early reconstruction of areas affected by the March 2011 disasters.

The ruling could also have an impact beyond South Korea.

At present, 23 countries and regions have import restrictions on Japanese food products.

China, which last year started easing its own restrictions on importing Japanese food items, may become more cautious going forward. Taiwan, which has been in a political bind after voters in a referendum last year approved keeping its import ban, will likely feel it has renewed justification to do so despite pressure from Japan.

In the wake of the ruling, Tokyo is expected to find it even more difficult to improve its relations with Seoul. The relationship has deteriorated partly due to a series of South Korean court rulings that ordered Japanese companies to pay compensation to South Koreans requisitioned to work for them during World War II, as well as the issue of “comfort women,” pundits said. The term refers to women who provided sex, including those who did so against their will, for Japanese troops before and during the war.

Last year a WTO dispute panel supported Japan, saying South Korea was wrong to keep its initial trade restrictions in place. But Thursday’s ruling overturned several key points of that verdict, saying South Korea’s measures were not overly restrictive and did not unfairly discriminate against Japan.

After a powerful earthquake and tsunami triggered a meltdown at the Fukushima No. 1 nuclear power plant on March 11, 2011, South Korea imposed a partial ban on fishery products from Fukushima and seven other prefectures due to fears of radioactive contamination. The other seven are Aomori, Iwate, Miyagi, Ibaraki, Tochigi, Gunma and Chiba.

South Korea widened its initial ban on Japanese fishery imports in 2013 to cover all seafood from the eight prefectures, and tightened testing requirements.

While dozens of countries imposed some sort of import restrictions on Japanese food products following the Fukushima crisis, Japan argued that the South Korean restrictions were far too strict.

After bilateral consultations reached a dead-end, Tokyo filed a complaint with the WTO in August 2015 over the restrictions, which covered 28 species of fish and mollusks.

Japan argued that radioactive levels were safe and that a number of other nations, including the United States and Australia, had lifted or eased Fukushima-related restrictions.

The dispute settlement panel said in February 2018 that the testing requirements and blanket ban were “more trade-restrictive than necessary” and broke WTO rules barring measures that “arbitrarily or unjustifiably discriminate” between members.

The panel recommended that the restrictions be lifted on the 28 species of fish and mollusks, including Alaska pollock and blue mackerel, as requested by Japan. Seoul appealed the decision in April that year.

South Korea imported ¥10.9 billion ($102 million) worth of Japanese seafood in the year to August 2013 before it broadened its restrictions. Those imports fell to ¥8.4 billion the following year, according to the Japanese government.