Taiwan condemned the "serious provocation" by China on Thursday after its military jets penetrated the island's air defence zone for two consecutive days this week.

Taiwanese authorities said multiple Chinese planes, including Su-30 fighter, J-10 fighter and Y-8 anti-submarine aircraft, intruded into Taiwan's Air Defense Identification Zone (ADIZ) during China's large-scale military exercises on Wednesday and Thursday.

"Military maneuvers by China's government constitute a serious provocation to Taiwan and a grave threat to regional peace and stability," the foreign ministry said in a statement.

"Today, the PLA has chosen to conduct exercises near Taiwan; tomorrow it may engage in similar threats near other countries."

The ADIZ stretches beyond Taiwan's airspace and is used to give an early warning of possible incursions. China maintains a similar air defence zone.

The ministry accused Beijing of "introducing a factor of extreme instability" in the region and urged the international community to pay close attention to its "growing aggressiveness."

"Taiwan does not seek confrontation, but neither will it back down," the statement said.

Foreign minister Joseph Wu also tweeted condemnation of the incursion, calling it a "threat against the country & regional peace."

China views democratic and self-ruled Taiwan as its own territory and has vowed to one day seize it, by force if necessary.

Beijing has ramped up diplomatic, economic and military pressure on Taiwan since the 2016 election of President Tsai Ing-wen, who refuses to acknowledge that the island is part of "one China".

Last month Taiwan said China sent fighter jets over a de facto border separating the two rivals in the Taiwan Strait during a high-profile visit by US health chief Alex Azar.