China to project its military further and stronger

China said on Tuesday it will project its military power further beyond its borders at sea and more assertively in the air, defending the construction of artificial islands which sparked concerns in Washington.

The People's Liberation Army navy will put a greater emphasis on "open seas protection", rather than "offshore waters defence" alone, the State Council, China's cabinet said in a white paper.

At the same time its air force will shift focus "from territorial air defence to both defence and offence", it said.

The army will increase its global mobility and artillery forces will strengthen capabilities for "medium and long-range precision strikes", it added.

The paper was released with China and the US at loggerheads over Beijing's rapid island building in contested parts of the South China Sea, which Beijing claims almost in its entirety.

China on Friday declared that its military "drove away" a US surveillance aircraft flying near the artificial islands, after US media witnessed a tense radio exchange.

A CNN television crew aboard a P-8 Poseidon plane recorded the Chinese navy issuing eight warnings and American pilots replying in each case that they were flying through "international airspace".

China has protested to Washington over the flight, calling it "highly irresponsible and dangerous" and warning that such actions could cause "unwanted incidents".

Beijing has increased annual spending on its military -- the largest by personnel in the world -- by double-digit annual percentages for several decades as it seeks to modernise its forces.

It has focused on increasing its naval power, commissioning its first aircraft carrier 2012 and rapidly adding to its submarine and surface fleets.

Several of its Asian neighbours, some also with claims in the South China Sea, have been alarmed by the military build up, though Beijing insists that its investment is purely defensive.

Military spokesman Yang Yujun said Tuesday that the island building was "beneficial to the whole of international society" because it aided China's search and rescue, and environmental protection work.

The white paper singled out the US' announced "rebalancing" towards Asia, and Japan's revision of some of its defence policies as objects of "concern".

"Such a development has caused grave concerns amongst countries in the region," it said without giving specifics.

It also said China's army would boost its online capabilities, after the US accused Chinese soldiers of cyber-hacking.

"China will expedite the development of a cyber-force," the paper said, without providing details.

China remains far behind the United States in military capacity and reach despite recent increases in defence spending.