The foreign ministry called in a senior Japanese diplomat on Tuesday to lodge a protest after Tokyo's latest annual diplomatic book repeated territorial claims to South Korea's easternmost islets of Dokdo.
Kim Jung-han, director general for Asia and Pacific affairs at Seoul's foreign ministry called in Hirohisa Soma, a senior official from the Japanese Embassy in Seoul, to express regret over the book's content and urge for Tokyo to retract the claims.
Soma walked into the ministry building at about 11 a.m., without taking questions from reporters.
The foreign ministry urged Japan to retract the claims.
"We strongly protest that Japan has renewed its unjust territorial claims to Dokdo, which is clearly our inherent territory, historically, geographically and by international law, and we urge for an immediate retraction of the claims," foreign ministry spokesperson Kim In-chul said in a commentary.
"We once again make it clear that the unjust claims by the Japanese government cannot affect in any way our sovereignty over Dokdo and that we will sternly act against any provocation on the islets."
In the book, Japan claimed that it is "contrary to the facts" to use the expression "sexual slavery" when referring to Korean victims who were forcibly taken by the Japanese military to work at frontline brothels during World War II and that South Korea agreed not to use the expression in a 2015 deal reached between the two countries to address the comfort women issue.
Japan's latest claim to Dokdo comes as bilateral relations remain chilled after months of discord stemming from pending wartime issues, including the unresolved issue of compensating Korean forced labor victims. South Korea was under Japan's colonial rule from 1910-45.
Unlike the versions of the past two years, Japan began to term South Korea "an important neighbor" again, according to Kyodo News, apparently to reflect Prime Minister Shinzo Abe's remarks describing Korea as such in parliamentary sessions in last October and in the beginning of this year.
Japan had called Korea a country that "shares strategic interests" in the 2017 version, but it has omitted that part for the past three years.
South Korea rejects the claims because the country regained independence from Japan's colonial rule and reclaimed sovereignty over its territory, including Dokdo and many other islands around the Korean Peninsula.
Since 1954, South Korea has stationed a small police detachment on Dokdo. (Yonhap)