The foreign ministry on Sunday called in a Japanese diplomat to lodge a protest over an annual regional event in Japan claiming sovereignty over Korea's easternmost islets of Dokdo. The ministry called in Hirotaka Matsuo, deputy head of mission at the Japanese Embassy in Seoul, to strongly protest the event that took place in Japan's western Shimane Prefecture. "(We) once again sternly urge for the immediate scrapping of the event," ministry spokesperson Park Il said in a statement. "Dokdo is clearly an integral part of our territory in terms of history, geography and international law." Park called on Tokyo to immediately stop its unjustified claims to the pair of rocky islets in the East Sea and face up to history in a humble manner. Dokdo has long been a recurring source of tension between Korea and Japan as Tokyo continues to make sovereignty claims in its policy papers, public statements and school textbooks. Korea has kept a small police detachment on Dokdo, called Takeshima in Japan, since its liberation from Japan in 1945.