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.