A group of South Koreans who were forced to work for a Japanese steel company during World War II have requested an asset seizure to force the company to compensate them as per a top-court verdict.

The proposal to confiscate assets of Nippon Steel & Sumitomo Metal Corp (NSSM) was recently made on an unspecified date by the lawyers representing four victims and their heirs, according to the local news agency Yonhap.

The decision is made based on the Supreme Court of South Korea's verdict that ordered the company on Oct. 30 to compensate South Korean workers who were forced to work at the company’s facilities, a decision opposed by the Japanese government.

The highest court upheld a 2015 decision ordering the company to pay compensation of 100 million won (about $89,000) to each of four South Koreans, of which only one is still alive.

The assets that have been legally requested for seizure are shares of a joint venture between NSSM and the main South Korean steel company, POSCO.

The value of the Japanese stake in that joint venture subsidiary, POSCO-Nippon Steel RHF (PNR), is worth about 11 billion won ($9.7 million), according to Yonhap.

The legal presentation was made known after the expiration of the deadline given to NSSM on Dec. 24 to pay compensation as demanded by the top South Korean court.

In addition to this case, on Nov. 29, the same court issued two similar verdicts against Mitsubishi Heavy Industries, demanding it to compensate 10 workers forced into labor during World War II.

These legal remedies have strained relations between South Korea and Japan, whose main joint challenge is the nuclear threat of Pyongyang, despite signs of a detente on the Korean Peninsula last year.

Japan occupied the Korean Peninsula between 1910 and 1945. At the end of World War II, the territory was divided in two, the North under the influence of the then Soviet Union and the South under that of the US, which led to the creation of two states in 1948.

The government of Japan has described these judicial rulings as "extremely regrettable and totally unacceptable,” saying it violates a previous bilateral agreement that already set compensation for colonization.

The Japanese government, which has announced its intention to resort to international courts, fears that the approximately 70 companies involved in 15 trials for the same reason may be subject to similar judgments.

According to Tokyo, the Japanese government has already paid substantial compensation to Seoul under a 1965 agreement, which normalized bilateral relations after the Japanese colonization period.

During its occupation of the Korean Peninsula in World War II, the Japanese Empire forcibly recruited hundreds of thousands of Koreans to feed their defense industry in the midst of war, in addition to committing other abuses that have been documented by historians.