A US Navy destroyer sailed near the China-claimed Spratly Islands in the South China Sea on Wednesday in a "freedom of navigation" operation, the 7th Fleet said.
The operation involving the guided missile destroyer Russell comes as China has rattled the region in recent years through large-scale island-building and base construction activities in the sea, including in the islands.
"Unlawful and sweeping maritime claims in the South China Sea pose a serious threat to the freedom of the sea," the fleet said in a statement. "The United States challenges excessive maritime claims around the world regardless of the identity of the claimant."
The Spratly Islands are claimed in whole or in part by China, Taiwan, Vietnam, Brunei, Malaysia and the Philippines.
Two aircraft carrier strike groups from the US Navy conducted a joint exercise on Feb. 9 in the South China Sea, in the first such exercise since US President Joe Biden took office in January.
A similar exercise involving two carrier strike groups was last held in the sea in July.
Meanwhile, the top uniformed officers of Japan and the US reaffirmed on Wednesday their commitment to oppose any unilateral attempts to change the status quo in the East and South China seas amid rising security concerns over China's recently enacted coast guard law, the Japanese Defense Ministry said.
Koji Yamazaki, the chief of the Self-Defense Forces' Joint Staff, said during a video conference with U.S. counterpart Mark Milley that the new law may not comply with international law and is "absolutely unacceptable," the ministry said.
China allows its coast guard to use weapons against foreign ships that it sees as illegally entering its waters under the new law. Its coast guard vessels were spotted near the Japanese-controlled Senkaku Islands in the East China Sea, also claimed by Beijing, for a record number of days last year.
The two generals' first talks under U.S. President Joe Biden's administration come as Chinese coast guard ships have entered Japan's territorial waters near the islands several times since the law took effect Feb. 1.
The legislation would target Japanese vessels navigating around the uninhabited islets called Diaoyu in China.
The two officers also agreed that the U.S. military plays an important role in promoting a "free and open Indo-Pacific" and they will step up their efforts to strengthen their ties for regional stability.
China has conflicting territorial claims with four of the 10 members of the Association of Southeast Asian Nations -- Brunei, Malaysia, the Philippines and Vietnam -- as well as Taiwan in the South China Sea.