China's newest military transport plane entered service Wednesday, the country's defence ministry said, extending Beijing's ability to deploy its fighting forces around the world as it pursues a greater global role.

The announcement comes with tensions mounting over territorial disputes between Beijing and its neighbours in the East and South China seas.

The Y-20 is the country's largest homegrown transport aircraft, a statement on the defence ministry's website said.

The plane is intended for moving troops and cargo over "long distances in diverse weather", it added.

Reports from its 2013 debut said the Y-20 has a maximum payload of 66 tonnes, which it can carry as far as 4,400 kilometres (2,700 miles).

With 55 tonnes on board it could fly from western China to Cairo.

At the time, experts told AFP that the true figures for the Y-20's maximum load and flying range were likely to be lower than those cited in state media due to the plane's reliance on a "very old" Russian-designed engine.

The plane's entry into service "marks a crucial step for the air force improving its strategic power projection capability," the official Xinhua news service quoted PLA Air Force spokesman Shen Jinke as saying.

For decades, China stuck to a strategy articulated by former paramount leader Deng Xiaoping, of "hiding its strength and biding its time".

But in recent years, it has conspicuously expanded its military's reach and taken a more aggressive stance on disputes on its periphery.

The construction of artificial islands capable of hosting military facilities in the South China Sea has raised tensions with rival claimants to regional waters, most notably Vietnam and the Philippines.

It has also earned the ire of the United States, which says a military buildup in the area will threaten the free transit of strategically important international waterways.

At the same time, China has also played a significant role in international policing efforts.

China is a major contributor to UN peacekeeping and has also assisted combatting piracy in the Gulf of Aden.

In November last year, it announced it would establish a naval facility in Djibouti, the strategically vital entrepot on the Horn of Africa.

The new aircraft will be used for "safeguarding national security as well as domestic and international rescue and relief work", Xinhua quoted Shen as saying.