Taiwan scrambled jets and navy ships on Wednesday as a group of Chinese warships led by China's sole aircraft carrier sailed north through the Taiwan Strait,the latest sign of heightened tensions between Beijing and the self-ruled Taiwan.

The Soviet-built Liaoning aircraft carrier, returning from exercises in the South China Sea, was not trespassing in Taiwan's territorial waters but entered its air defense identification zone (ADIZ) in the southwest, Taiwan's defense
ministry said.

As a result Taiwan scrambled jets and navy ships to “surveil and control” the passage of the Chinese ships through the narrow body of water separating Taiwan and China.

“We have full grasp of its movements,” Taiwan defense ministry spokesman Chen Chung-chi said.

Taiwanese military aircraft and ships have been deployed to follow the carrier group, which is sailing up the west side of the median line of the strait. he said.

China has said the Liaoning aircraft carrier was on drills to test weapons and equipment in the disputed South China Sea and its movements comply with international law.

The latest Chinese naval exercises have unnerved Beijing's neighbors, especially Taiwan which Beijing claims as its own, given long-running territorial disputes in the South China Sea.

China claims most of the energy-rich waters 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.

China distrusts Taiwan President Tsai Ing-wen and has stepped up pressure on her following a protocol-breaking, congratulatory telephone call between her and U.S. President-elect Donald Trump last month.

Beijing suspects Tsai wants to push for the island's formal independence, a red line for the mainland, which has never renounced the use of force to bring what it deems a renegade province under its control.

Tsai says she wants to maintain peace with China.