The debut of China's first aircraft carrier marks a symbolic milestone for the growing military power, but analysts said the second-hand vessel remains far from a strategic game-changer.

China officially put the vessel into service on Tuesday, flexing its muscle just as Asian maritime rivalries are at boiling point with China and Japan locked in an increasingly hostile dispute over islands in the East China Sea.

China's military and political leadership have portrayed the 300-metre (990-foot) "Liaoning" as a quantum leap forward in naval capability at a time when the United States says it is making a strategic "pivot" toward Asia.

But without the rest of the battle group or the planes to go with it, the new hardware is more of a symbolic first step that may give the navy some prestige but does not dramatically change its military options, analysts say.

At a commissioning ceremony in the northeastern port of Dalian, Premier Wen Jiabao called the carrier's launch a "milestone" in Chinese military history and weapons development.

Yang Yi, a rear admiral in China's navy, said in a commentary in state-run media that the hulking vessel moves the country closer to fulfilling a national destiny to "not only be a land power but also a sea power".

Tensions in the East China Sea have risen dramatically in recent months over islands known as the Diaoyus to Beijing and claimed by Tokyo as the Senkakus.

China is locked in a similar row with Vietnam and the Philippines in the South China Sea.

With the carrier, "China will have more variable ways, both strong and soft, to solve the disputes in the East and South China seas", Qiao Liang, an air force major general and leading author on military affairs, told state media.

Analysts note that China still lacks proven carrier-borne aircraft and that the second-hand retro-fitted ship brings China little closer to developing its own carrier force.

"This carrier is more of a stepping stone for further development," said Arthur Ding, a Taiwan-based expert on China's military.

Ding said the vessel would have a "psychological impact" on the region due to its symbolism, but was "unlikely to change the overall balance of power overnight" as it was intended mainly as a training platform for any future Chinese-made carrier.

Ukraine built the vessel for its navy in the 1980s, eventually selling its stripped-down hulk to Beijing in 1998. It was later towed to China, which installed engines and navigation systems.

But developing fixed-wing aircraft and training pilots capable of landing on the carrier is another matter, Ralph Cossa, a military analyst with the Center for Strategic and International Studies in Honolulu, told AFP.

"Carrier operations are not easy. Refitting the ship is one thing. Developing a carrier-based air wing is another," he said.

China is developing J-15 strike aircraft, possibly for use on the carrier. Pictures have emerged on Chinese websites of aircraft on the carrier's flight deck, but China's capabilities are unproven.

"You cannot call a ship an aircraft carrier without aircraft," Qiao was quoted by state media as saying, although he added that he was confident China would soon be able to field a carrier-based air wing.

The Liaoning -- named for the northeastern Chinese province -- is not expected to be a fully operational aircraft carrier for another three years at least, and a domestically made carrier is even further in the future.

China has become increasingly assertive over its longtime maritime territorial claims as its economic and military power have expanded, causing rising anxiety among its neighbours.

But even when it is operational, the Liaoning has little hope of countering the smaller but technologically superior US-backed Japan Maritime Self-Defense Force, letting alone the US Seventh Fleet, Cossa said.

"I can't see them trying to sail their unarmed carrier into the East China Sea to pressure the Japanese, not for a few more years anyway," he said.

Still, analysts said China has to start somewhere and the Liaoning will "add some prestige" and allow the Chinese navy to "cast a bigger shadow" on the region's seas, Cossa said.

At the very least, this could give China a further intimidating edge over its smaller rivals, such as the Philippines, he added.