United States (US) Secretary of State Marco Rubio spoke with Philippine Secretary of Foreign Affairs Enrique Manalo over China’s “dangerous and destabilizing actions” in the South China Sea (SCS).

In a statement on Thursday (Manila Time), US State Department spokesperson Tammy Bruce said Rubio conveyed that China’s behavior “undermines regional peace and stability and is inconsistent with international law.”

China has maintained its presence in parts of the SCS, which encroaches on the Philippines’ sovereign rights in its exclusive economic zone in the West Philippine Sea.

“The Secretary underscored the United States’ ironclad commitments to the Philippines under our Mutual Defense Treaty,” Bruce noted.

According to Bruce, both secretaries also “exchanged views on ways to advance security cooperation, expand economic ties for shared prosperity, and deepen avenues” for further cooperation in the Indo-Pacific region.

Rubio and Manalo stressed the importance of the alliance between Manila and Washington as President Donald Trump returns to the White House.

“We discussed the importance of the PH-US alliance for the prosperity and security of the Indo-Pacific, and the strength of our bilateral political, economic, and people-to-people ties,” Manalo wrote in his X (formerly Twitter) post on Wednesday.

“We look forward to working with Secretary Rubio and his team toward addressing challenges and sustaining the momentum and positive trajectory in our bilateral relations.”

President Ferdinand Marcos Jr. earlier expressed his eagerness to collaborate with returning US President Trump on various issues that “will yield mutual benefits to two nations with deep ties, shared beliefs, common vision, and a long history of working together.”

Last week, during the confirmation of his appointment, Rubio mentioned the continuing presence of the China Coast Guard’s largest vessel, called “The Monster Ship,” in Philippine waters.

“This massive ship that the Chinese have built, that's like headed towards the Philippines, and the Philippines feels threatened by it, rightfully so,” Rubio lamented.

He then reiterated Washington's "iron-clad" commitment to the Philippines-US mutual defense treaty amid China's continuing intimidation against Manila.

“We've seen this on a daily basis with the harassment and so forth, but on a daily basis, if, God forbid, there is some miscommunication or some inadvertent conflict emerges there, and we have obligations to them, the impact that will have on the entire globe, the impact that it will have on the entire globe is enormous,” he said.