The U.S. Navy chief said on Monday he hoped the deployment of two aircraft carriers on a training mission in East Asia would deter any attempts to destabilize the region, where military tensions have risen amid China's growing assertiveness.

The U.S. carriers John C. Stennis and Ronald Reagan began joint operations in seas east of the Philippines at the weekend in a show of strength ahead of an international court ruling expected soon on China's expansive territorial claims in the contested South China Sea.

Adm. John Richardson, the chief of U.S. Naval Operations, told a Washington think tank it was not often the United States had two carrier strike groups in the same waters and it was a sign of U.S. commitment to regional security.