The defence ministry said it scrambled aircraft to broadcast warnings after 36 fighter jets, 12 H-6 nuclear-capable bombers and four other planes entered its southwest air defence identification zone (ADIZ).

Four more fighters entered the zone in a night sortie, bringing the total to 56 planes, the ministry added.

The Mainland Affairs Council (MAC), Taiwan's top China policy-making body, accused Beijing of "seriously damaging the status quo of peace and stability in the Taiwan Strait" with its recent string of incursions.

"We demand the Beijing authorities immediately stop its non-peaceful and irresponsible provocative actions," MAC spokesman Chiu Chui-cheng said in a statement.

"China is the culprit for causing tensions between the two sides of the (Taiwan) Strait and it has further threatened regional security and order," he added, saying Taiwan "will never compromise and yield" to threats.

The ADIZ is not the same as Taiwan's territorial airspace but includes a far greater area that overlaps with part of China's own air defence identification zone and even includes some of the mainland.

Self-ruled democratic Taiwan lives under the constant threat of invasion by China, which views the island as its territory and has vowed to one day seize it, by force if necessary.

In the last two years, Beijing has begun sending large sorties into Taiwan's defence zone to signal dissatisfaction at key moments -- and to keep Taipei's ageing fighter fleet regularly stressed.

Nearly 150 Chinese warplanes had breached Taiwan's ADIZ since Friday when Beijing marked its National Day with its then-biggest aerial show of force, buzzing the island with 38 planes.

That was followed by another incursion by 39 planes on Saturday, sparking criticism from Washington.

State Department spokesman Ned Price reiterated Monday that the United States was "very concerned" by the "provocative" moves by Beijing.

"This activity is destabilising, it risks miscalculation and it undermines regional peace and security," Price told reporters.

"We strongly urge Beijing to cease its military, diplomatic and economic pressure and coercion against Taiwan," he said, calling US commitment to the island "rock-solid".

- Ramping up pressure -

China's foreign ministry on Monday accused Washington of sending out "an extremely wrong and irresponsible signal" with "provocative" actions such as selling arms to Taipei and sending its warships to the Taiwan Strait.

"The US should correct its mistakes, earnestly abide by the 'one China Principle'... prudently and appropriately handle the Taiwan issue, stop bolstering 'Taiwanese independence' separatist forces," said spokeswoman Hua Chunying.

Beijing has ramped up pressure on Taiwan since the 2016 election of President Tsai Ing-wen, who rejects its stance that Taiwan is part of "one China".

Under President Xi Jinping, Chinese warplanes are crossing into Taiwan's ADIZ at an unprecedented rate.

Last year, a record 380 Chinese military jets made incursions into Taiwan's defence zone, and the number this year as of early October has already exceeded 600.

Last week, 24 Chinese warplanes flew into the zone after Taiwan applied to join a major trans-Pacific trade pact, a move Beijing has opposed.

Friday's show of force came the same week China accused Britain of "evil attentions" after it sent a frigate to sail through the Taiwan Strait, which Beijing claims as its own waterway.

Xi has described Taiwan becoming part of the mainland as "inevitable".

US military officials have begun to talk openly about fears that China could consider the previously unthinkable and invade.

Monday's incursion "was a way for Beijing to tell Washington that it will not submit to US warnings, that it, not Washington, sets the rules in this part of the world," said J. Michael Cole, a Taipei-based analyst at the University of Nottingham's Taiwan Studies Programme.