Taipei says it has sent six warships and eight air force aircraft to "stand guard" and monitor the Chinese ships that passed the island on their way to drills in the South China Sea.

The Shandong aircraft carrier is docked at a naval port in Sanya in southern China's Hainan Province, December 17, 2019
The Shandong aircraft carrier is docked at a naval port in Sanya in southern China's Hainan Province, December 17, 2019 (AP)

An aircraft carrier group led by China's newest carrier, the Shandong, has sailed through the Taiwan Strait on its way to routine drills in the South China Sea, China's navy said, after Taiwan mobilised its forces to monitor the trip.

While it is not the first time China's carriers have passed close to Taiwan, it comes at a time of heightened tension between Taipei and Beijing, which claims the self-ruled island as its territory.

The Shandong carrier group sailed through the Taiwan Strait a day after a US warship transited the same waterway. China's military said it tailed the ship.

China's navy said the Shandong and its accompanying ships had "smoothly" transited the sensitive and narrow Taiwan Strait on Sunday, heading for exercises in the South China Sea, where China has extensive and disputed territorial gains.

The drills are part of "normal arrangements made in accordance with annual plans", it said. 

"In the future, we will continue to organise similar operations based on training needs."

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Taiwan stands defiant

Taiwan's Defence Ministry said the Shandong was accompanied by four warships and had set out from the northern Chinese port of Dalian on Thursday.

Taiwan said it sent six warships and eight air force aircraft to "stand guard" and monitor the Chinese ships' movements.

Taiwan has complained of repeated Chinese military activity, including China's regular flying of air force aircraft near the island.

China says such drills are aimed at protecting the country's sovereignty.

Beijing has been angered by increased US support for Taiwan, including new arms sales and visits to Taipei by senior US officials, further straining already poor Sino-US ties.

Taiwan President Tsai Ing-wen is overseeing a revamp of the island's military, rolling out new equipment such as "carrier killer" stealth corvettes.

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China seeking to hone carrier operations

The Shandong is China's second carrier and was formally commissioned almost exactly a year ago.

Since then, it has successfully completed tasks such as carrier-based aircraft take-off and landing and use of its weapons, the Chinese navy said.

"The combat capability of the formation system has been continuously improved in experimental training," it added, referring to the group of warships which accompany the Shandong.

The Asian power claims almost all of the islands of the South China Sea, territorial claims disputed by other countries in the region including Vietnam, Malaysia, the Philippines and Brunei.

To counter China, the US has been sending ships to the region more frequently to carry out what it calls "freedom of navigation" operations.

To maintain a strategic advantage over the Chinese Navy whose "battle force has more than tripled in size in only two decades," the US Navy plans to modernise with smaller, more agile and even remotely piloted ships.

Source: Reuters