The top diplomats of Japan, the United States and South Korea agreed Thursday to pursue closer cooperation in addressing North Korea's steady development of nuclear and missile capabilities, and its expanding military cooperation with Russia.

"Cooperation and coordination with our closest allies is more important than ever," U.S. Secretary of State Antony Blinken said as he met with his Japanese and South Korean counterparts, Yoko Kamikawa and Cho Tae Yul, in Rio de Janeiro, citing regional challenges also including "increasingly assertive actions" by China.

In addition to North Korea, Blinken, Kamikawa and Cho discussed efforts to maintain peace and stability across the Taiwan Strait and the ongoing Israel-Hamas war, according to the U.S. State Department's top spokesman, Matthew Miller.

Japanese Foreign Minister Yoko Kamikawa (far L) attends a meeting with her U.S. and South Korean counterparts in Rio de Janeiro on Feb. 22, 2024. (Kyodo)

While confirming support for each country's Indo-Pacific strategies, Miller said the three also reiterated in their discussion of Gaza the urgent need to secure the release of all hostages and boost humanitarian assistance to Palestinian civilians amid the conflict.

The three-way talks, Cho's first since assuming his post last month, took place on the sidelines of a foreign ministerial meeting of the Group of 20 major economies.

Since U.S. President Joe Biden hosted a trilateral summit with the leaders of Japan and South Korea in August last year, the three countries have been stepping up coordination over a range of issues including North Korea, which has repeatedly fired ballistic missiles in violation of U.N. Security Council resolutions.

"Looking at the global landscape, the free and open international order, based on the rule of law, is now being challenged," the department quoted Kamikawa as saying. "Our strategic coordination is more important than ever, and I am eager to work even more closely with both of you in dealing with North Korea and beyond."

During the meeting, which lasted about an hour, the trio had a "frank exchange of views" on China, a Japanese Foreign Ministry official said.

The foreign ministers of Japan, the United States and South Korea last held in-person talks in San Francisco in November.

North Korea has been strengthening its military ties with Russia, which is engaged in a war with Ukraine. U.S. officials have accused North Korea of providing missiles to Russia for use in the war that started about two years ago.

The top diplomats' meeting in the Brazilian city also came after North Korea's state-run media reported recently that leader Kim Jong Un's sister Kim Yo Jong, in a rare statement, had suggested a possible visit to Pyongyang by Japanese Prime Minister Fumio Kishida.

She reiterated that the issue of North Korea's abductions of Japanese nationals in the 1970s and 1980s has already been settled, and said Kishida's visit could take place if Tokyo does not make the issue a "stumbling block" for future relations between the two countries.

The Japanese official disclosed that Kamikawa had told Blinken and Cho that Japan remains open to dialogue with North Korea to ease tensions, fueled by Pyongyang's frequent ballistic missile tests, while also expressing concern over its deepening ties with Russia.

The official, however, declined to go into details, including whether the Japanese foreign minister had touched on the North Korean statement.

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