In a move likely to stoke the ire of Beijing, the U.S. Navy's Carrier Strike Group 1, which includes the Nimitz-class aircraft carrier USS Carl Vinson, began what the navy called "routine operations" in the contested South China Sea on Saturday.

Beijing had warned Washington last week not to challenge its sovereignty in the strategic waterway amid reports that the U.S. Navy was gearing up to sail more warships near China's man-made islands in the contested waters.

China claims most of the strategic waters, through which $5 trillion in trade passes each year. The Philippines, Vietnam, Malaysia, Taiwan and Brunei also have overlapping claims.