South Korea expressed strong protest Tuesday over Japan's renewed claims to the East Sea islets of Dokdo in an annual defense policy paper, calling for Tokyo to immediately retract its "futile" claims.

The ministries of foreign affairs and national defense called in Hirohisa Soma, deputy chief of mission at the Japanese Embassy in Seoul, and Col. Takashi Matshmoto, a defense attache, respectively, to lodge a protest.

"Our government strongly protests Japan's futile territorial claims to Dokdo, which is our inherent territory historically, geographically and by international law, and urges it to immediately retract the claims," Choi Young-sam, foreign ministry spokesman, told a regular press briefing.

"The government makes it clear again that the Japanese government's wrongful argument has no impact on our sovereignty over our territory, Dokdo, and that we will respond to any provocation over Dokdo in a grave, stern manner," he added.

Earlier in the day, Japanese Defense Minister Nobuo Kishi reported this year's defense white paper laying claim to Dokdo during a Cabinet session led by Prime Minister Yoshihide Suga.

Tokyo's claims came as the two countries have been in talks over the possibility of President Moon Jae-in attending the opening ceremony of the Olympic Games later this month and having talks with Suga to help address protracted rows over wartime history and trade.

Tokyo repeated the claims in the white paper for the 17th consecutive year, dampening the mood for regional cooperation in the lead-up to the Summer Games slated for July 23-Aug. 8.

Territorial tensions already resurfaced due to the inclusion of the East Sea outcroppings in the map of the route of the Tokyo Olympic torch relay, which had triggered calls here for a boycott of the Games.

The 2021 paper stated that the territorial issue over Dokdo and the four disputed islands also claimed by Russia remains "unresolved."

This year's white paper took on more provocative hues, as its cover carried an image of Samurai, a warrior in a pre-modern Japan -- evocative of Tokyo's wartime atrocities, particularly for victims of Japan's past militarism, like South Korea.

Dokdo has long been a recurring source of tension between the two neighbors, as Tokyo continues to make the sovereignty claims in its policy papers, public statements and school textbooks.

South Korea has been in effective control of Dokdo, with a small police detachment, since its liberation from Japan's 1910-45 colonial rule. (Yonhap)