BEIJING: China on Tuesday commissioned its first aircraft carrier amid an escalating tussle with Japan over ownership of disputed islands. The carrier would primarily be used for testing purposes but it will also help defend “the interests of state sovereignty, security and development,” the country’s defense ministry said.

Chinese president Hu Jintao and premier Wen Jiabao attended the commissioning ceremony highlighting the political importance attached to the 990-foot Liaoning, as the Soviet-era acquisition is called. The launch of the vessel at the Dalian port makes China the last of the five-member UN Security Council to own an aircraft carrier.

A total of 10 countries own such giant ship while others like India are set to enter the club. India’s efforts to acquire an aircraft carrier from Russia have been delayed by five months. The carrier, rebuilt from the Soviet ship Varyag, was renamed “Liaoning” and underwent years of refitting efforts to install engines, weapons, as well as a year-long sea trial.

“The delivery and commission of the first carrier is a milestone in the PLA's history and embodies a major achievement of China's weaponry and equipment development, as well as its national defence modernization,” Wen said.

The Liaoning enters naval service on a day Beijing published a white paper to assert its “indisputable sovereignty” over the Diaoyu/Senkaku Islands, which is currently under Japanese control. Japan on Tuesday fired water cannons on dozens of fishing boats from Taiwan that tried to approach Diaoyu islands to show their solidarity towards China.

“The delivery and commission of the Liaoning is just a small step of China's aircraft carrier programme and there is a long way to go before we have a powerful navy,” the ship’s commander Captain Zhang Zheng was quoted as saying by the official Xinhua news agency. “Today will be forever remembered as the day China's Navy has entered the era of aircraft carriers.”

Xinhua tried to strike a assuring tone saying in a commentary: “There is no need of panic about whether China has an aircraft carrier or how many aircraft carriers China has.”

The Chinese Navy did not disclose the type of aircrafts that will be operated from the carrier. But the Chinese media had earlier indicated that the Sukhoi-30 aircraft, renamed as J-15, would carry out ‘circuits and landing approach’ trials.

Questions have been raised by Indian and other foreign experts about the carrier’s capabilities. Kamlesh Kumar Agnihotri of the New Delhi-based National Maritime Foundation has expressed doubts about the capability of China’s J-15 aircraft to effectively operate out of the carrier. “While the carrier may be ‘floating’ and ‘moving’, the ultimate aim would lie in achieving the most vital milestone of ‘being able to fight’. Therein lies the major challenge in transforming Varyag into a quintessential fighting machine,” Agnihotri said in a recent article.

The Liaoning will be run by highly educated crew including female sailors. Half of the commissioned officers on board hold masters or doctoral degrees, Mei Wen, political commissar of the carrier, said.