Prime Minister Shinzo Abe says he wants South Korea to uphold promises that form the basis of relations between the two countries.
Abe spoke to reporters in Hiroshima City on Tuesday about the countries' deteriorating ties.
He said the most important issue is trust over bilateral agreements.
Abe said South Korea unilaterally carried out actions that run counter to a 1965 agreement that settled the right to seek compensation for wartime labor.
He said South Korea is violating the treaty that became the basis for normalized diplomatic ties.
Abe emphasized Japan's position remains consistent and is based on international law. He urged South Korea to respond appropriately.
Abe also spoke about how Japan will respond to a US-led naval plan to ensure safety in the Strait of Hormuz.
He stressed that safe passage of ships is vital for Japan's energy security. He said Japan will make a decision after considering various factors, including the stable supply of oil and relations with the United States and Iran.