U.S. Secretary of State Marco Rubio engaged in discussions on Wednesday with his Philippine counterpart regarding China’s “dangerous and destabilizing actions in the South China Sea,” reaffirming the United States’ “ironclad” commitment to defense support for Manila.

According to a statement from the U.S. State Department, Secretary Rubio emphasized that China’s conduct threatens regional peace and stability and contravenes international law during his conversation with Foreign Minister Enrique Manalo.

Over the past two years, the Philippines has faced ongoing maritime disputes with China, frequently encountering tensions over contested areas within Manila’s exclusive economic zone in the South China Sea.

Rubio’s conversation with Manalo came after he hosted a meeting with counterparts from Australia, India, and Japan in the “Quad” forum, which focuses on China-related issues, the day following President Donald Trump’s return to the White House. The four nations reaffirmed their commitment to collaborative efforts.

Members of the Quad, along with the Philippines, share concerns regarding China’s expanding influence, and analysts noted that the meeting was intended to convey a message of continuity in the Indo-Pacific strategy, with countering Beijing identified as a primary focus for the Trump administration. During his call with Manalo, Rubio reiterated the United States’ steadfast commitments to the Philippines under their Mutual Defense Treaty and explored avenues to enhance security cooperation, strengthen economic relations, and foster regional collaboration, as stated in the announcement.

In the lead-up to Trump’s inauguration, the Philippines and the United States conducted their fifth round of joint maritime exercises in the South China Sea, continuing their collaborative efforts initiated in 2023. Under the leadership of Philippine President Ferdinand Marcos Jr., security cooperation between the two nations has significantly increased, as he has moved closer to Washington and permitted the expansion of military bases accessible to American forces, including those positioned near Taiwan, an island claimed by China but governed democratically.

During a visit to the Philippines last week, Japanese Foreign Minister Takeshi Iwaya indicated that a trilateral initiative aimed at enhancing cooperation, which was established by Japan, the U.S., and the Philippines at a summit last year, would be further strengthened with the transition to the new U.S. administration in Washington.