BEIJING - No amount of interference or shadowing of its aircraft will stop the Chinese air force from carrying out long-range drills, the defense ministry said, announcing another round of exercises of the type that have unnerved Taiwan and Japan.

• China air force says to continue with flight drills at sea - CCTV

The air force carried out further long-range exercises on Thursday, the ministry said late that same day, without giving details of where they happened.

Such "normal" drills accord with international law and practices and are part of an "ordinary need" to raise combat abilities and strengthen the military, it added.

• Chinese air force carries out long-range drills in Pacific

"No matter what obstructions are encountered, the Chinese air force will carry on as before; no matter who flies with us, the Chinese air force will fly a lot and as normal!" the ministry added, citing an air force spokesman.

Drills over the past few months have mostly focused on flying near self-ruled Taiwan, claimed by China as its own, and by Japan's southern island chain to the north of Taiwan.

Taiwan's military said earlier this month it was on a high state of alert following three straight days of drills by the Chinese air force near it.

China has been increasingly asserting itself in territorial disputes in the South and East China Seas. It is also worried about Taiwan, run by a government China fears is intent on independence.

Beijing has never ruled out the use of force to bring proudly democratic Taiwan under its control, and has warned that any moves towards formal independence could prompt an armed response.

China is in the midst of an ambitious military modernisation programme that includes building aircraft carriers and developing stealth fighters to give it the ability to project power far from its shores.

Taiwan is well armed with mostly U.S. weaponry, but has been pressing Washington to sell it more high-tech equipment to better deter China. (Reporting by Ben Blanchard; Editing by Michael Perry)