A Chinese aircraft carrier led a group of warships Monday through disputed South China Sea waters near Taiwan, escalating already mounted tensions between Beijing and its self-ruled rival. China's only aircraft carrier, the Liaoning, and five warships passed approximately 90 miles south of the Taiwan-controlled Pratas Islands in what China called a routine exercise.

The move resulted in air and naval forces being put on high-alert in Taiwan, which Beijing considers part of its territory, and drew a response from Taiwanese officials. "Staying vigilant and flexible has always been the normal method of maintaining airspace security," said Taiwanese defense ministry spokesperson Chen Chung-chi, according to Reuters.

The political conflict between China and Taiwan was reignited earlier this month when President-elect Donald Trump spoke on the phone with Taiwanese President Tsai Ing-wen. Since 1979, the U.S. has officially acknowledged China's claim to Taiwan and has forgone any formal diplomatic relations with the island.

Trump's hardline rhetoric toward China's trade policies has Beijing concerned that the billionaire real estate tycoon-turned-politician could upset the current state of U.S.-China relations and Beijing launched a formal complaint following news of the telephone conversation. Relations between the U.S. and China were further strained when a Chinese naval vessel seized a U.S. underwater drone last week.

China also concerned U.S. allies Sunday when its Soviet-built aircraft carrier set sail for the Western Pacific toward Japan in the carrier's first operation in "distant sea waters." Though Japan stated its borders had not been breached, China's vast territorial claims in the East China Sea, near Japan's southern islands and the Koreas, and the South China Sea, near Taiwan, Brunei, Malaysia, the Philippines and Vietnam, have created a point of contention between Beijing, regional players and Washington.