China's first home-built aircraft carrier has left dock in the northeastern port of Dalian to begin sea trials of its engine, propulsion and navigation systems, state media said on Sunday.

The trials represent a landmark in Beijing's extensive project to modernize its navy as it continues to build up its presence in the disputed South China Sea and around Taiwan, which it sees as its own territory.

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Soviet style

The Type 001A carrier, which has yet to be named, is expected to be commissioned by 2020. Building commenced in November 2013.

It is China's second aircraft carrier following the purchase of the Soviet-built Liaoning from Ukraine in 1998. The Liaoning went into service in 2012 after being refitted in China.

Neither of the two vessels is nuclear-powered; instead, they use conventional oil-fueled steam turbine power plants for propulsion.

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Catching up

The new carrier, which has a cruising speed of 31 knots, is based on the same Soviet Kuznetsov-class design used for the Liaoning, with a ski-jump type ramp for taking off, unlike US carriers, which have more advanced catapult technology. Like the older ship, it can carry some 40 planes.

A third aircraft carrier is being built in Shanghai, according to state media, although the Defense Ministry has yet to confirm this.

Although China's 2-million strong military is the largest in the world and its navy is also the biggest in terms of numbers of ships, its defense budget in 2018, though raised, is still only about one-quarter that of the United States. The US has 11 carriers, all nuclear-powered.

Chinese state media have quoted experts as saying that the country needs at least six carriers.

China last year established its first overseas military base in Djibouti, in the Horn of Africa, and its navy has recently deployed its ships further into the Pacific and Indian oceans.

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tj/jm (AFP, Reuters, dpa, AP)

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