US, ROK, Japan leaders agree closer cooperation over DPRK

US President Joe Biden, center, meets with the Republic of Korea President Yoon Suk -yeol, left, and Japan's Prime Minister Fumio Kishida, right, during the NATO summit in Madrid, June 29, 2022. Seated behind Biden is, from left, White House national security adviser Jake Sullivan, Secretary of State Antony Blinken, Secretary of Defense Lloyd Austin, and National Security Council Director for the Korean Peninsula and Mongolia Adam Farrar. (SUSAN WALSH / AP)

MADRID – The leaders of the United States, the Republic of Korea and Japan on Wednesday expressed deep concern over missile tests by the Democratic People’s Republic of Korea and said they would cooperate more closely to address the issue.

US President Joe Biden, Japanese Prime Minister Fumio Kishida and ROK President Yoon Suk-yeol met on the sidelines of the NATO summit in Madrid.

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Japan-ROK ties have long been strained by memories of Japan’s occupation of the Korean Peninsula from 1910 to 1945

The DPRK has this year been conducting missile tests at an unprecedented pace.

The three leaders agreed to explore further means to reinforce "extended deterrence" against the DPRK along with security cooperation.

"The deterrence capabilities of the Japan-US and US-Republic of Korea alliances need to be upgraded as part of the essential effort to strengthen the trilateral partnership between Japan, the US, and ROK," Kishida said.

The ROK and Japanese leaders are attending NATO's annual summit as observers for the first time. 

Ties between Japan and the ROK have long been strained by memories of Japan’s occupation of the Korean Peninsula from 1910 to 1945.

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Relations deteriorated to their worst in years under previous ROK President Moon Jae-in, with spats over territory and history and the two nations calling off an intelligence sharing pact. Yoon, though, has expressed a desire to repair ties, and Kishida has also seemed to respond favorably.