A Japanese Maritime Self-Defense Force destroyer flying the controversial rising sun flag entered a South Korean port Monday to attend a naval drill scheduled for later this week, amid recovering ties between the two neighbors.

South Korea's effective acceptance of the port call by the MSDF in Busan despite the ship bearing the flag, viewed by critics as a symbol of Japan's wartime militarism, suggests that Seoul no longer considers it problematic.

Japan colonized the Korean Peninsula for 35 years from 1910. The flag was used by the Imperial Japanese Army and Navy until the end of World War II in 1945.

A Japanese Maritime Self-Defense Force destroyer flying the rising sun flag arrives at a port in Busan, South Korea, on May 29, 2023, to participate in a naval drill scheduled to be held on May 31 off Jeju Island. (Kyodo) ==Kyodo

Last week, Japanese Defense Minister Yasukazu Hamada said the destroyer would display the rising sun flag at the drill, set to be held off Jeju Island on Wednesday, "in accordance with" domestic legislation that mandates MSDF vessels fly the flag as their official ensign.

In 2018, Japan canceled its participation in a naval event in South Korea after Seoul demanded that Tokyo refrain from displaying the rising sun flag on its vessels. At the time, bilateral relations had plunged to their lowest point in decades under former President Moon Jae In.

Meanwhile, the administration of Moon's successor Yoon Suk Yeol, who took office in May 2022 pledging to improve ties with Japan to tackle North Korea's missile and nuclear threats, has recognized displaying the rising sun flag is a "normal international custom."

In November, crew members of a South Korean supply vessel saluted MSDF ships flying the rising sun flag at a naval review held in Japan, causing Yoon's government to draw criticism from opposition parties at home.

MSDF vessels bearing the rising sun flag joined international naval events held in South Korea in 1998 and 2008.

In March, Yoon proposed a solution to a long-standing bilateral dispute over compensating wartime laborers. In a sign of thawing ties, Japan and South Korea have resumed reciprocal visits between their leaders, following their suspension in December 2011.

The United States, Australia and Canada are also slated to attend the upcoming drill, which will aim to strengthen capabilities for countering the proliferation of weapons of mass destruction, the South Korean Defense Ministry said.

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