U.S. President Joe Biden hosted Japanese Prime Minister Fumio Kishida and Philippines President Ferdinand Marcos Jr. at the White House on Thursday, aiming to send China a clear message that it must halt its aggressive behavior in the South China Sea.

"United States defense commitments to Japan and to the Philippines are ironclad," Biden said at the trilateral summit.

There has been rising tension between Manila and Beijing. In recent weeks, Chinese Coast Guard ships have taken provocative actions to block resupply missions for Philippine soldiers stationed on the Second Thomas Shoal, who guard Manila's sovereignty claims over the Spratly Islands.

"Facing the complex challenges of our time requires concerted efforts on everyone's part, a dedication to a common purpose and an unwavering commitment to the rules-based international order," Marcos said, couching his words in diplomatic terms often used to target Beijing.

"Multilayered cooperation between allies and like-minded countries is essential if we are to maintain and bolster a free and open international order based on the rule of law," Kishida reiterated.