TOKYO -- Japan is considering taking a dispute with South Korea over its compensation for wartime forced laborers to the International Court of Justice as the deadline for seeking third-country arbitration passes on Thursday, public broadcaster NHK reported.

The question of compensation for South Koreans for labor during Japan’s 1910-45 occupation of the Korean peninsula has soured the U.S. allies’ relations, which took a turn for the worse this month when Japan restricted exports of high-tech material to South Korea.

South Korea’s Supreme Court last year ordered two Japanese companies to compensate the wartime workers in a ruling that Tokyo said violated international law. Japan believes the issue of compensation was settled under a 1965 treaty.

With no mutually palatable agreement, Tokyo has pushed for third-party arbitration, which Seoul has rejected. Midnight (1500 GMT Thursday) is the deadline for making those arrangements, Japanese deputy chief cabinet secretary Yasutoshi Nishimura said.

Nishimura told a regular briefing that Tokyo had not received any word on Seoul’s decision. He added the government would continue to “strongly urge” its neighbor to accept the arbitration procedure.

NHK said that once the deadline passes, Japan would continue to push Seoul for proposals to end the dispute while preparing for countermeasures - including considering going to the International Court of Justice.

The case cannot go to trial, however, without agreement from South Korea, Kyodo news agency reported.

Officials at Japan’s foreign ministry were not immediately available to comment.

Japan initially cited the dispute over compensation for the wartime laborers as being behind what it sees as broken trust with South Korea when it announced tighter export controls this month. Tokyo has stressed that the controls were not retaliation over the forced-labor dispute.

In a separate report, Kyodo news cited Japanese government sources as saying Tokyo would reject Seoul’s request to hold another working-level meeting to discuss the export controls.

The most recent one, held last week in Tokyo, stoked tensions further as the two sides publicly contested the accounts of their frosty meeting.

South Korea has appealed to ally United States to defuse the tension with Japan, warning of threats to global supplies memory chips and smartphones.

A senior South Korean government official said on Wednesday the export curbs could hurt global technology companies including the operations of Samsung in the Texas state capital of Austin.

During a visit to Seoul on Wednesday, David Stilwell, the top U.S. diplomat for East Asia policy, said the United States would “do what it can do” to help, but did not elaborate on what those steps might be and said it was fundamentally up to South Korea and Japan to resolve their differences.