US Secretary of State Antony Blinken talked individually with his South Korean and Japanese counterparts, underlining the significance of "sustained... trilateral cooperation" ahead of his trip to China, according to the State Department.

Blinken informed South Korean Foreign Minister Park Jin on Friday of the US' "ironclad commitment" to South Korea's defense, according to State Department Spokesperson Matthew Miller.

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He added that "the Secretary and the Foreign Minister condemned the DPRK's continued unlawful ballistic missile launches and noted the need for the PRC to use its influence to encourage Pyongyang to engage in serious and sustained diplomacy."

Blinken echoed the "ironclad commitment" to defense to Japan's Minister for Foreign Affairs Hayashi Yoshimasa Saturday and "condemned the DPRK’s continued unlawful ballistic missile launches into the Sea of Japan."

Joint statement against DPRK's launches

The three countries released a joint statement Thursday to "condemn" the DPRK's launch of two short-range ballistic missiles, just after Pyongyang warned of an "inevitable" retaliation to ongoing joint military maneuvers between the US and South Korea.

Tokyo unveiled a major defense overhaul last year, pledging to boost security spending to two percent of GDP by 2027 and calling China the "greatest strategic challenge ever" for Japan.

The trilateral statement underlined the developing rapprochement between Japan and South Korea, a key foreign policy priority of "Biden's administration in the face of regional concerns and China's expanding influence."

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Blinken also told Park, though not Hayashi, of the US pledge to "responsibly manage the US-PRC relationship."

He is set to visit China on Sunday and Monday on the first trip by a top US diplomat in nearly five years. The visit was rescheduled after a planned trip to Beijing in February was canceled when Washington claimed to have detected – and later shot down – a Chinese balloon.

Biden told reporters Saturday morning that he intended to meet with Chinese President Xi Jinping "over the next several months" to discuss "legitimate differences we have but also how... to get along."