US Defense Secretary Lloyd Austin has condemned activities targeting Philippine vessels in the South China Sea, without directly naming China. He also underscored the importance of continued dialogue to avoid accidental clashes.

Austin was speaking at an Asian security forum, the Shangri-La Dialogue, in Singapore on Saturday. The defense officials of Asian and Western nations are taking part.

Recently, Chinese Coast Guard ships have repeatedly obstructed the movement of Philippine vessels near the Second Thomas Shoal, such as by using water cannons. The Philippines effectively controls the shoal but Beijing claims it.

Austin said, "Harassment that the Philippines has faced is dangerous."

He indicated that the United States will boost cooperation with like-minded countries, including Japan.

Austin touched on his meeting with Chinese Defense Minister Dong Jun on Friday. The defense chiefs of the two countries met in person for the first time since November 2022.

Austin said, "There is no substitute for direct military to military talks between senior leaders," adding that there was no substitute for open lines of communications to avoid "misunderstanding and miscalculations."

Philippines President Ferdinand Marcos Jr. indicated on Friday that if a Filipino is killed at sea as a result of aggressive Chinese action, it would invoke a mutual defense treaty with the US.

Asked how Washington would interpret such a case, Austin said he would not speculate on any hypothetical situation. But he said his country's commitment to the mutual defense treaty with Manila is "ironclad."