TOKYO (Reuters) - Japan on Wednesday demanded talks with South Korea over a Korean court compensation award against a Japanese company for using forced laborers during World War Two, saying all such claims were settled decades ago.

South Korean Ambassador to Japan Lee Su-hoon is surrounded by media after a meeting with Japanese Vice Minister for Foreign Affairs Takeo Akiba (not in picture) at the Foreign Ministry in Tokyo, Japan, in this photo taken by Kyodo January 9, 2019. Mandatory credit Kyodo/via REUTERS ATTENTION EDITORS - THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY. MANDATORY CREDIT. JAPAN OUT. NO COMMERCIAL OR EDITORIAL SALES IN JAPAN.

South Korea, for its part, called for calm.

Ties between the Asian neighbors have been frosty since the court ruled in October that Nippon Steel & Sumitomo Metal Corp should pay 100 million won ($90,500) to each of four South Korean plaintiffs.

The court on Tuesday approved a request by the plaintiffs to seize assets held by Nippon Steel in South Korea.

Japan’s Foreign Ministry summoned South Korea’s ambassador to demand consultation, based on an article of a 1965 treaty that normalized ties between the two sides.

It was the first time the article had been invoked, the ministry said.

Japanese Chief Cabinet Secretary Yoshihide Suga told a news conference that the court decision was “extremely regrettable”.

South Korea’s foreign ministry called for Japan to keep calm.

“Causing unnecessary conflicts and animosity doesn’t help resolve the problem at all,” the ministry said in a statement. “It is necessary to manage the situation in a cool-headed and cautious manner.”

Nippon Steel said its joint venture with South Korean steelmaker POSCO had received a notice from the court.

Asked whether it has any direct impact on the company’s South Korean business, a company spokeswoman declined to comment.

“We will consult with the Japanese government and take an appropriate measure,” the spokeswoman said.

She reiterated that there was no change in the company’s stance that all matters concerning wartime reparations were settled under the 1965 agreements.

POSCO declined to comment and there was no immediate comment from South Korea’s foreign ministry.

Japan has urged South Korea to take appropriate steps to avoid measures unfair to Japanese companies.

The two countries share a bitter history that includes Japan’s 1910-45 colonization of the Korean peninsula, the forced mobilization of labor at Japanese companies and the use of comfort women, Japan’s euphemism for girls and women, many of them Korean, forced to work in its wartime brothels.

The rows over wartime history have long been a hurdle for relations at a time when there is a need for concerted efforts to dismantle North Korea’s nuclear and missile programs.

The two sides are also embroiled in a dispute over whether a South Korean warship had locked its targeting radar on a Japanese patrol plane last month.