China's second aircraft carrier is "taking shape" after two years and nine months of construction, local media reported, a move likely to further unnerve Taiwan and other neighbours about Beijing's growing military assertiveness.

Construction of The Shandong, named after a province in China's east coast, began in 2014, the APP of Shandong television and radio said in a report seen on Tuesday.

The Shandong, China's first indigenous aircraft carrier, is "taking shape", the report said. It did not give a date for completion or further details.It was being built in the northeastern port of Dalian, the Defence Ministry has said.

The country's first aircraft carrier, The Liaoning, was bought from Ukraine in 1998 and refitted in China.

In January 2017 a group of Chinese warships, led by The Liaoning, tested weapons and equipment in the South China Sea in what the Chinese Foreign Ministry described as routine exercises that comply with international law.The group of warships sailed through waters south of Japan and then rounded east and south of Taiwan in December on their way to the southern Chinese province of Hainan.

But China is years away from perfecting carrier operations similar to those the United States has practised for decades.The eventual launch of The Shandong would further rattle self-ruled democratic Taiwan, which Beijing claims as its own, as well as Asian neighbours Brunei, Malaysia, the Philippines, Taiwan and Vietnam with disputed claims in the South China Sea.China and Taiwan have been diplomatic and military rivals since 1949 when Nationalist, or Kuomintang, troops lost the Chinese civil war to the Communists on the mainland and fled to the island.Bilateral trade, investment and tourism have grown significantly in the past three decades, but tensions have been simmering since the island elected President Tsai Ing-wen from the independence-leaning Democratic Progressive Party last year.

China has vowed to attack if the island declared de jure independence.