Images showing construction on China's "third and largest aircraft carrier" (image: Reuters)

China is constructing its first full-sized aircraft carrier dubbed Type 002, a carrier that seems smaller than 100,000-tonne US carriers but larger than France`s 42,500-tonne Charles de Gaulle, according to reports.

Center for Strategic and International Studies (CSIS), Washington, provided images to Reuters that revealed considerable recent activity in the last six months on a large vessel at the Jiangnan shipyard outside Shanghai.

"From what we can see there has been a lot of activity in the last six months or so. It would appear that it is the third carrier, and if it is not, it's hard to envisage what other large vessel it would be," CSIS analyst Matthew Funaiole told Reuters.

The CSIS images show a bow section that appears to end with a flat 30-metre (98-foot) front and a separate hull section 41 metres wide, with gantry cranes looming overhead.

Fabrication halls the size of several soccer pitches have been built nearby, and work appears to be continuing on a floodable basin, possibly to float the finished hull into the nearby Yangtze River estuary.

"While details regarding the Type 002 are limited, what is observable at Jiangnan is consistent with what is expected for the People`s Liberation Army Navy's third aircraft carrier," said the CSIS ChinaPower analysis, published on its website Tuesday.

The Pentagon said last week that work on what is expected to be China`s first large, modern platform capable of leading a full range of strike group operations, had begun.

In its annual report on China`s military modernisation, issued last Friday, it noted that the third carrier would probably be larger than the first two and fitted with a catapult launch system to accelerate aircraft during takeoff.

"This design will enable it to support additional fighter aircraft, fixed-wing early-warning aircraft, and more rapid flight operations," the report said.

There is no clarity regarding the kind of catapult that would be used and whether the carrier will be nuclear-powered, military analysts say.

"Once completed, it will outclass any warship from any Asian country, including India and Japan," said Ian Storey, of the ISEAS Yusof Ishak Institute. "It is yet another indication that China has emerged as Asia`s paramount naval power."

China`s first two carriers are relatively small, with only up to 25 aircraft, less than half the number aboard US carriers, and have jump ramps built into their bows. That configuration limits not just the types of aircraft that can fly off them, but how much weaponry and fuel they can carry.

Its first carrier, the Liaoning, was a Soviet-era Ukrainian ship bought secondhand in 1998 and re-fitted in China. The Liaoning had been seen as more of a training platform for teaching personnel the tricky art of carrier operations. In April, the ship began to play a combat role following recent modifications and intensive training exercises.

A still-unnamed second carrier based on that design, launched in 2017, was built locally. The second carrier has been undergoing sea trials from its base in northern Dalian and is not expected to enter service until 2020.

China's Ministry of Defence did not respond to a request for comment.