This photo taken on December 23, 2016 shows Chinese J-15 fighter jets being launched from the deck of the Liaoning aircraft carrier during military drills.

China's sole aircraft carrier conducted drills in the South China Sea, the navy said, days after neighboring Taiwan said the carrier and accompanying ships had passed 90 nautical miles south of the island amid renewed tension between the two sides.

The Soviet-built Liaoning aircraft carrier and accompanying warships sailed round the east coast of Taiwan in what China called a routine exercise complying with international law.

The carrier's J-15 fighters conducted flight exercises in "complex sea conditions" on Monday, the People's Liberation Army Navy said on its official microblog late the same day.

The carrier group also ran helicopter exercises, it said, but did not give details on the exact location.

China claims most of the South China Sea through which about $5 trillion in ship-borne trade passes every year. Neighbors Brunei, Malaysia, the Philippines, Taiwan and Vietnam also have claims.