The United States has sought to reassure the Philippines — its oldest ally in the Asia-Pacific — that its commitment to the country’s defense remains “ironclad” amid rising tensions with China, with U.S. President Joe Biden and Philippine leader Ferdinand Marcos Jr. also agreeing on the need to bolster “trilateral nodes of cooperation” with Japan.

Marcos, who on Monday became the first Philippine leader to visit the White House in a decade, emphasized the importance of the more than 70-year-old alliance, saying that the region was facing “arguably the most complicated geopolitical situation in the world right now.”

“It is only natural for the Philippines to look to its sole treaty partner in the world to strengthen and to redefine the relationship that we have and the roles that we play in the face of those rising tensions that we see now around the South China Sea and Asia-Pacific and Indo-Pacific regions,” Marcos said ahead of his talks with Biden.