The exercises were also in response to Beijing's army restricting the airspace off the Chinese coast.

"In response to these actions by the PLA, the MND has initiated combat readiness drills, factoring in enemy threats, weather conditions, and tactical positioning," the defence ministry said in a statement, adding that military units were on "high" alert.

There was no immediate public announcement by the PLA or Chinese state media about increased military activity around Taiwan.

China insists Taiwan is part of its own territory and regularly deploys fighter jets and navy ships to press its claims of sovereignty.

There has been intense speculation about the possibility of China launching military drills in response to Taiwan President Lai Ching-te's Pacific tour last week that included two stopovers on US soil.