South Korea on Tuesday issued a strong protest after Japan reaffirmed its claim to disputed islets in the Sea of Japan, also known as the East Sea.
Tokyo included the claim in its 2025 Diplomatic Bluebook, stating that Seoul "illegally occupies" the islets.
Known as Takeshima in Japan and Dokdo in South Korea, the islets have been under South Korean control since 1954, with a coast guard unit stationed there.
"We strongly protest against the repetition of the unjust territorial claim to Dokdo, which is clearly our territory based on history, geography and international law," a South Korean Foreign Ministry statement said.
"We urged (Japan) to immediately withdraw this," it added.
The ministry said it would respond firmly to "any kinds of provocations by Japan" regarding Dokdo.
It also summoned Taisuke Mibae, deputy head of the Japanese Embassy in Seoul, to lodge a formal protest, according to Yonhap news.
