Senior diplomats from Japan, the United States and South Korea agreed Wednesday to deepen their trilateral cooperation in achieving the complete and irreversible denuclearization of North Korea, the Japanese Foreign Ministry said.

During their talks in Tokyo, the diplomats also affirmed the importance of maintaining peace and stability across the Taiwan Strait claimed by mainland China while condemning any attempts to change the status quo in the East and South China seas, according to the ministry and the U.S. State Department.

(From L) South Korean First Vice Foreign Minister Choi Jong Kun, Japan's Vice Foreign Minister Takeo Mori and U.S. Deputy Secretary of State Wendy Sherman pose for a photo in Tokyo on July 21, 2021. They discussed regional security issues including their bid to get North Korea to abandon its nuclear weapons program. (Pool photo) (Kyodo) ==Kyodo

South Korea, however, made no mention of any issues related to Taiwan or Beijing's assertiveness during the conference or in its statement released afterward, reflecting Seoul's diplomatic balancing act between its defense ally, the United States, and China, a key economic partner.

The meeting among Japanese Vice Foreign Minister Takeo Mori, U.S. Deputy Secretary of State Wendy Sherman and South Korean First Vice Foreign Minister Choi Jong Kun came as the U.S. administration of Joe Biden sees trilateral cooperation as a key element in promoting security in Asia and keeping China in check.

Sherman said at the joint press conference that should there be any action that undermines the rules-based international order, the three countries will counter it together.

"We will strive to enhance our closer, broader trilateral ties" in dealing with issues, including that related to the Taiwan Strait, Mori said at the same news conference that followed the first deputy-foreign ministerial talks by the three nations since October 2017.

But relations between Japan and South Korea remain sour amid wartime history and other disputes, prompting the United States on Tuesday to urge them to work cooperatively on "common regional and international priorities."

The three diplomats also agreed to use the trilateral framework to respond to the coronavirus pandemic and climate change.

Regarding the denuclearization of North Korea, they agreed to work out ways for Washington to resume dialogue with Pyongyang in line with the Biden administration's recent review of U.S. policy toward the reclusive state.

The United States and South Korea expressed full support for Japan's request to seek understanding and assistance in resolving past abductions of Japanese nationals by North Korean agents, the ministry said.

The three also agreed on the need to work closely with the Association of Southeast Asian Nations to realize a free and open Indo-Pacific initiative promoted by Japan and the United States.

The talks followed a Japan-U.S. bilateral meeting on Tuesday in which Mori and Sherman agreed to boost cooperation against China's assertive behavior, while Mori and Choi in a separate meeting remained divided over issues involving wartime history even as they agreed to continue the dialogue.

China lays claim to the Senkaku Islands, a group of uninhabited Japanese-administered islets in the East China Sea. It has frequently sent its coast guard vessels near the islets, which it calls Diaoyu, including in Japan's territorial waters, despite protests from Tokyo.

China also has overlapping claims with its neighbors in the South China Sea and has raised concerns by militarizing outposts in disputed areas.

When the top U.S., Japanese and South Korean envoys on North Korea met face to face in Seoul last month, they reaffirmed the need to work closely toward complete denuclearization of the Korean Peninsula through the early resumption of dialogue with Pyongyang.

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