During his visit to the Philippines, US Secretary of State Antony Blinken conveyed the message of the United States' "ironclad" commitments to "defend the ally in armed attack in the South China Sea".

At a joint press conference with his Philippine counterpart Enrique Manalo, Blinken said, "These waterways are critical to the Philippines, to its security, to its economy, but they're also critical to the interests of the region, the United States, and the world," adding: "That's why we stand with the Philippines and stand by our ironclad defense commitments, including under the mutual defense treaty."

Blinken also toured a semiconductor plant and described the island of the Philippines as "an increasingly critical partner" in ensuring a "resilient" supply chain of chips.

He is set to meet with Marcos on Tuesday as part of an Asia tour to showcase support for regional allies against China, also serving as a prequel to a trilateral meeting in the US next month between US President Joe Biden, Philippines President Ferdinand Marcos, and Japanese Prime Minister Fumio Kishida.

After announcing the trilateral meeting, White House Press Secretary Karine Jean-Pierre said the leaders would encourage a "shared vision for a free and open Indo-Pacific".

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That same statement was reiterated last month when the Philippines and the United States conducted a joint military drill in the South China Sea in a series of military exercises to expand the Philippines' military presence in the region. 

This marks the third military exercise conducted by both countries in collaborative efforts, increasing provocations against China, which regards the US presence in the region as an interference in Chinese and regional affairs. 

Filipino Armed Forces Chief Romeo Brawner stated that the joint drill "demonstrates our commitment to a free and open Indo-Pacific, and fosters close cooperation towards further enhancing our maritime capabilities." 

Ever since the US and the Philippines launched joint military naval exercises, bilateral relations between China and The Philippines saw sharp declines, adding to the existing tensions and territorial conflicts.