Escalating diplomatic tensions with South Korea, Japan formally issued the Diplomatic Blue Book 2012 that reiterated its claims that Dokdo is Japanese territory historically and under international law.
Seoul's foreign ministry called in Matsuo Hirotaka, the political counselor at the Japanese embassy in Seoul, and lodged a formal protest against the renewed claim to Dokdo, ministry spokesman Cho Byung-jae said.
South Korea "expresses deepest regret over Japan's wrongful claim to jurisdiction over Dokdo, which is clearly the territory of the Republic of Korea, in its Diplomatic Blue Book 2012, released on April 6," Cho said, referring to South Korea by its official name.
"Any claim by Japan to Dokdo is meaningless," Cho said. "Japan should recognize this fact and stop reiterating such reckless claims.
"As long as Japan makes territorial claims to Dokdo from a distorted view of history, their pledge to 'build a future-oriented Korea-Japan partnership' will be nothing but hollow words."
The presidential office also accused Japan of sticking to "unreasonable insistence."
"Dokdo is South Korean territory and our island in the East Sea," presidential spokesman Park Jeong-ha said. "However hard Japan tries to do so, Dokdo will remain in its place" as South Korean territory, he said.
Dokdo (Yonhap file photo)
Dokdo, which lies closer to South Korea in the body of water that divides the Korean Peninsula and Japan, has long been a thorn in relations between the two countries. South Korea keeps a small police detachment on the islets, effectively controlling them.
South Korea rejects Japan's claim to Dokdo as nonsense because the country regained its independence from Japanese colonial rule and reclaimed sovereignty over its territories, including Dokdo and many other islands around the Korean Peninsula.
The latest move by Japan is expected to prompt heated reactions in South Korea and follows Tokyo's approval of school textbooks for high-school students last month that also reassert the Japanese claim to Dokdo.
In a statement, the Northeast Asian History Foundation, a Seoul-based history think tank, accused Japan of issuing the diplomatic paper that "denies not only historical facts but also the reality that the Republic of Korea exercises territorial sovereignty over Dokdo."
"We sincerely hope that the Republic of Korea and Japan will serve as true partners in promoting peace and prosperity in Northeast Asia," the think tank said.
"To that end, the Japanese government must abandon its groundless claims of sovereignty over Dokdo."