South Korea’s two largest metropolises on Friday each adopted an ordinance labeling Japanese firms suspected of employing forced labor and producing military supplies during World War II as “war crimes companies.”

The legislative body of the southern port city of Busan passed its measure in the morning, becoming the first municipality in the country to do so, and the Seoul Metropolitan Council in the capital followed suit in the afternoon.

Their decisions come as bilateral ties are increasingly strained over historical and territorial disputes. Whether it will have an actual impact on the companies concerned is unknown.

Under the nonbinding ordinances, 284 companies including Mitsubishi Heavy Industries Ltd. are to be given the designation, and the cities have also been asked not to purchase products from them in the future.

Busan also enacted a provision that stickers saying “product of a war crimes company” be attached to such products that have already been purchased.

Commenting on the Busan ordinance, Chief Cabinet Secretary Yoshihide Suga slammed it as being “based on an inappropriate and irrational claim.”

“Such an ordinance takes aim at certain Japanese companies and could inflict economic damage. It’s extremely regrettable,” he told a news conference in Tokyo.

Mitsubishi Heavy is one of the Japanese enterprises ordered by South Korean courts last year to compensate Koreans who claimed they were victims of forced labor.

The companies have refused to comply in line with Japan’s stance that South Korea waived its rights to compensation under a 1965 accord accompanying a treaty that set up diplomatic relations between the countries.

Similar bills have been submitted in other city councils but were rejected due to worries they could further worsen ties between South Korea and Japan. The bilateral relationship has been inflamed by the court rulings and an ongoing trade spat.

Even so, calls by politicians for boycotts of Japanese products have drawn criticism in some quarters, with their moves seen as an attempt to pander to the public.

According to the Chosun Ilbo, a major South Korean daily, when the proposal was first submitted, some members of the Seoul legislature voiced opposition, saying public authorities cannot restrict bidding qualifications against companies because of their actions during the war.

The Busan City Council also passed an ordinance allowing for the erection of monuments commemorating historical events.

The move appears to be aimed at giving legal protection to the installation of controversial statues in front of the Japanese consulate in the city.

Earlier this year, authorities in the port city removed a statue symbolizing Korean victims of forced labor that had been placed by a civic group in front of the consulate.

In 2017, the city adopted an ordinance allowing it to protect statues symbolizing “comfort women.” The term is a euphemism used to refer to women who provided sex, including those who did so against their will, for Japanese troops before and during World War II.

Last month, a section of a major art festival in Aichi Prefecture featuring a statue symbolizing such comfort women shut down following a flurry of protests.

One of the exhibits on display at the Aichi Triennale 2019 held in Nagoya was the “Statue of a Girl of Peace,” which drew violent threats.

The decision came at a time when diplomatic ties between Japan and South Korea have fallen to arguably the lowest level ever amid disputes over wartime history and trade policy.