South Korea's Foreign Ministry lodged a strong protest Tuesday against Japan's renewed assertion of its unjust sovereignty claim over Dokdo, the easternmost sovereign islets of South Korea, in its annual report on diplomatic policy.

A Japanese diplomat was also summoned by the Foreign Ministry less than two hours after the ministry's spokesperson, Lim Soo-suk, issued a formal denunciation.

"The government strongly protests against the Japanese government's repeated inclusion of unjust sovereignty claims over Dokdo, which is clearly an integral part of our territory historically, geographically and under international law, in its Diplomatic Bluebook released on April 16," read a commentary issued under the name of Foreign Ministry’s spokesperson.

"The government urges the Japanese government to immediately withdraw such claims."

The Diplomatic Bluebook is an annual publication by Japan's Foreign Ministry, outlining Japan's foreign policy objectives and activities.

"The government once again makes it clear that any claim by the Japanese government regarding Dokdo, the inherent territory of the Republic of Korea, cannot in any way affect our sovereignty," the commentary read, referring to South Korea by its official name.

"We clearly affirm that we will continue to respond firmly in the future."

South Korea's Foreign Ministry also summoned Taisuke Mibae, the deputy chief of mission at the Japanese Embassy in Seoul, on Tuesday morning. Mibae, who was called in by Seo Min-jung, director general for Asia and Pacific affairs at the Foreign Ministry, did not respond to requests for comments at the building of the Foreign Ministry.

The 2024 Diplomatic Bluebook claimed that "Takeshima is indisputably an inherent territory of Japan both in light of historical facts and based on international law."

Dokdo is known as Takeshima in Japan.

The diplomatic paper also reiterated Japan's position that South Korea has "continued its illegal occupation of Takeshima with no legal basis in international law," a claim consistently included in Japan's diplomatic papers since 2018.

However, South Korea was labeled as an "important neighboring country" in this year's diplomatic policy paper, which underscored the imperative to "expand cooperation and collaboration in various fields and to work together as partners to pave the way for a new era."

Japan referred to South Korea as a "partner" for the first time since the 2010 Diplomatic Bluebook.

The Diplomatic Bluebook stated that "there has never been a time when close cooperation between both countries is more necessary than now, in light of the challenging security environment in the Indo-Pacific region."

The diplomatic paper also highlighted the importance of South Korea and Japan further enhancing cooperation on global issues as bilateral relations get back on track for improvement.

However, the Diplomatic Bluebook reaffirmed Japan's refusal to accept the South Korean court rulings mandating Japanese companies to compensate Korean victims of wartime forced labor, which took place during Japan's occupation of the Korean Peninsula from 1910 to 1945.

The diplomatic paper said the Japanese government protested, considering the rulings, including one in 2024 Feb. in which deposit money paid by Japanese firm Hitachi Zosen to a South Korean court was transferred to a plaintiff, as "extremely regrettable and absolutely unacceptable."

The spokesperson's commentary only addressed Japan's claim of sovereignty over Dokdo. However, during the meeting between Seo and Mibae, they discussed various topics including compensation for forced labor victims, a senior Foreign Ministry official said Tuesday on condition of anonymity.

However, Lim noted positive aspects of the Diplomatic Bluebook, highlighting that it "devotes a substantial portion" to explaining the South Korean government's third-party reimbursement system and made a positive assessment during Tuesday's regular briefing. The system is designed to compensate Korean victims of Japanese wartime forced labor through a Korean government-affiliated foundation.

Lim further elaborated that South Korea noted "certain improvements in the depiction of South Korea compared to the previous year, including the incorporation of the term 'partner' to define the relationship with Korea."

"We hope to closely work together in building a future-oriented Korea-Japan relationship as we approach the 60th anniversary of diplomatic relations next year," Lim said.