China on Tuesday dispatched its sole aircraft carrier on its first training mission to the South China Sea amid rising tensions with neighbouring countries over the ownership of islands in the region and Beijing marking an air defence zone over waters in dispute with Japan.
The Liaoning, of Ukrainian origin and refitted in China, left its base in the eastern Chinese city of Qingdao on what the government called a "scientific and training mission".
It was "the first time the carrier has conducted a cross-sea training voyage since it was commissioned into the People's Liberation Army (PLA) Navy last year," Liaoning's Captain Zhang Zheng told the state media.
The aircraft carrier was escorted by two missile destroyers, the Shenyang and Shijiazhuang, and two missile frigates, the Yantai and Weifang.
The Liaoning and its crew conducted a series of tests and training drills, including landing and takeoff by various aircraft, including the J-15 carrier-borne fighter.
State media added that the upcoming South China Sea trial is a normal arrangement in the carrier's scheduled training, according to the PLA Navy.
The move by China comes a day after it the defence ministry said it had lodged formal protests with the US and Japanese embassies after both countries criticised a Chinese plan to impose new rules on airspace over disputed waters in the East China Sea.
The timing of the carrier being sent on a training schedule to the choppy waters of the South China Sea could be interpreted as a show of China's growing naval aspirations and strength.
China claims almost the entire oil and gas-rich South China Sea with overlapping claims put up by from Taiwan, Malaysia, Brunei, the Philippines and Vietnam.
Beijing has also refuted Japan's criticism over China's newly established Air Defense Identification Zone (ADIZ) over the East China Sea.
State media reported that in Tokyo, Chinese ambassador to Japan Cheng Yonghua rejected the protest lodged by Japanese deputy foreign minister Akitaka Saiki, saying the setup of ADIZ is a normal move in the world and accords with international laws and practices.
He said the ADIZ will not affect the freedom of flight over the East China Sea, and urged Japan to stop irresponsible and groundless entanglement.
In Beijing, according to a report state-run Xinhua news agency, assistant Chinese foreign minister Zheng Zeguang lodged representation with Japanese ambassador to China Kitera Masato over Tokyo's response to China's establishment of ADIZ on Saturday.
Zheng said that the ADIZ aims to defend China's national sovereignty and its territorial and airspace security, as well as safeguard the flight order over the East China Sea, stressing it conforms to the UN charter.