An annual ceremony was held in western Japan on Thursday to press the country's claim to a group of South Korea-controlled islets in the Sea of Japan, a long-standing sticking point in bilateral ties that have recently been improving.

Shimane Gov. Tatsuya Maruyama urged the central government to promote talks with South Korea toward a solution of the territorial dispute over Takeshima at the commemoration day event organized by the prefectural government. The islets are called Dokdo in South Korea.

"Takeshima is an inherent territory of Japan," Maruyama said, underscoring that the prefectural government will put more efforts in "securing territorial rights" to the islets and pursue related research studies.

An annual event to mark Shimane Prefecture-designated "Takeshima Day" is held in Matsue, western Japan, on Feb. 22, 2024, to push Japan's claim to a group of South Korea-controlled islets in the Sea of Japan. (Kyodo) ==Kyodo

Shojiro Hiranuma, a Cabinet Office parliamentary vice minister, said at the event that South Korea's "illegal occupation cannot be tolerated," and added that the central government aims to peacefully resolve the issue through diplomatic negotiations in line with international law.

The Shimane government designated Feb. 22 as "Takeshima Day" in 2005, a century after a Cabinet decision was issued placing them under the prefecture's jurisdiction. The event commemorating that decision has been organized for the past 19 years.

The ceremony saw a Cabinet Office parliamentary vice minister attend for the 12th straight year, although the local government has repeatedly asked the central government to dispatch a higher-ranking official to the event.

Later on Thursday, the South Korean Foreign Ministry summoned Taisuke Mibae, deputy chief of mission at the Japanese Embassy in Seoul, to lodge a protest with Japan over the Shimane event.

The islets, covering a total land area of 0.2 square kilometer and located roughly 200 km from either country, consist of volcanic rock with little vegetation or drinking water. But they are located in rich fishing grounds.

South Korea has stationed security personnel on the islets since 1954 and taken effective control of them.

Bilateral relations, which had deteriorated in the late 2010s and early 2020s to the worst level in decades, have seen notable signs of improvement since South Korean President Yoon Suk Yeol took office in May 2022.

Although disputes stemming from Japan's 1910-1945 colonial rule of the Korean Peninsula and the territorial issue linger, Prime Minister Fumio Kishida and Yoon have sought to deepen ties between their nations and with their key ally, the United States, to tackle common challenges, especially a nuclear-armed North Korea.

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