Japanese officials may soon get a fresh diplomatic headache stemming from its colonialist past with South Korea as it struggles to cope with the sex slave denial issue, a territorial dispute and challenges to the naming of the Sea of Japan.

The government is paying close attention to a lawsuit filed in South Korea by those conscripted to work for Japanese companies during the war. Speculation is growing that the South Korean Supreme Court will rule in favor of the plaintiffs in the first half of 2014.

A court victory for the former workers, who are seeking withheld wages and compensation from the firms, may effectively overturn the terms of the 1965 bilateral agreement that settled wartime compensation issues and established diplomatic ties.