SEOUL – South Korea's foreign ministry summoned a Japanese diplomat on Tuesday to protest a claim in Japan's annual diplomatic policy Bluebook over a group of islands between the countries at the center of a longstanding territorial row, Yonhap news agency reported.

The disputed islets lying halfway between the two countries are called Dokdo by South Korea and Takeshima by Japan.

South Korea restored its sovereignty over Dokdo after the Korean Peninsula's liberation from the 1910-45 Japanese colonization

Earlier, South Korea's foreign ministry said that it "strongly protests" Japan's unjust claims made in the Diplomatic Bluebook, and that the islands were historically and geographically its sovereign territory.

The ministry urged Tokyo to immediately retract its territorial claims, which will have no impact on South Korea's sovereignty over Dokdo, vowing to firmly respond to relevant issues.

Every year since 2005, Japan has laid territorial claims to the rocky outcroppings in its diplomatic blue and defense white papers.

South Korea restored its sovereignty over Dokdo after the Korean Peninsula's liberation from the 1910-45 Japanese colonization. Seoul has since been in effective control of the islets, with a small police detachment deployed.

South Koreans regard Japan's territorial claims to the islets as a denial of colonial history as Dokdo was the very first territory that was forcibly occupied by Imperial Japan.