Japan is prepared to take various measures against South Korea, Foreign Minister Taro Kono said Wednesday, as relations between the two countries have further deteriorated over the issue of compensation for wartime labor.

“We are ready to take a range of countermeasures should they become necessary,” Kono told a Lower House budget committee session.

His remarks came after lawyers for South Korean plaintiffs said last week they would start the process of liquidating seized assets of Nippon Steel & Sumitomo Metal Corp.

In October, South Korea’s top court ordered the steel-maker to pay compensation for wartime forced labor during Japan’s 1910-1945 colonial rule of the Korean Peninsula, a ruling that Tokyo has described as a breach of an accord inked with Seoul decades ago.

Japan has criticized the order based on the view that the two countries settled the issue of compensation “finally and completely” with the 1965 pact.

Tokyo has been urging Seoul to launch consultations to resolve their dispute, while threatening to take countermeasures as calls on the government to take a harder stance have been growing among ruling party lawmakers.

Raising tariffs on South Korean imports is seen as one option.

Escalating diplomatic friction further, South Korean National Assembly Speaker Moon Hee-sang recently called for an apology from Emperor Akihito to resolve a separate dispute over the issue of “comfort women,” a euphemism used to refer to women who provided sex, including those who did so against their will, for Japanese troops before and during World War II.