South Korea Tuesday protested Japan's foreign policy report that renewed Tokyo's claim to South Korea's easternmost islets of Dokdo, Yonhap News Agency reported.
In the 2015 Diplomatic Bluebook, released earlier in the day, the Shinzo Abe administration argued that the pair of outcroppings in the East Sea is Japanese territory based on historical facts and international law.
It came a day after Japan's education ministry irked South Koreans by unveiling the results of its regular review of textbooks for middle school students.
Seoul's foreign ministry summoned Kenji Kanasugi, a minister at the Japanese Embassy in Seoul, to lodge a complaint with the Japanese government.
Japan's move, which South Korean officials describe as a provocation, apparently undermined efforts to improve relations between the neighboring nations. Seoul-Tokyo ties have long been strained despite brisk economic and cultural exchanges due to long-standing stand-offs over territory and shared history.