Lawyers representing South Korean plaintiffs in a World War II labor court case against Japan's Nippon Steel & Sumitomo Metal Corp. have set a Dec. 24 deadline for the firm to show willingness to discuss a court verdict on compensation.

If the firm fails to respond, the lawyers, who spoke after being denied a meeting with company officials for a second time on Tuesday, said they would start procedures to seize its South Korean assets.

Tuesday's incident stemmed from a ruling by South Korea's Supreme Court late in October that Nippon Steel must pay 100 million won ($90,500) to each of four South Koreans for forced labor during the war.

The Japanese government has denounced the verdict, saying all wartime reparations were dealt with in a 1965 treaty that normalized ties between the two nations.

At the time of the ruling, Nippon Steel called it "extremely regrettable," but added that it would review the decision carefully in considering further steps.

On Tuesday, the lawyers visited Nippon Steel's Tokyo headquarters for a second time, only to be turned away at reception, said Lim Jae-sung, one of the attorneys.

The lawyers left documents at reception regarding the case, Lim told a briefing at the Foreign Correspondents' Club of Japan.

Lim said two options for seizing Nippon Steel's assets include shares of PNR, a joint venture between Nippon Steel and South Korean steel company POSCO, and intellectual property the company owns in South Korea.

The Japanese firm confirmed that it refused to meet the lawyers because its stance has not changed, a company spokeswoman said, adding that the company had received a letter, although she did not comment on the contents.

Asked about the Dec. 24 deadline, the spokeswoman said the company would consult the Japanese government and take appropriate action.