China conducted Sunday major military exercises involving troops from multiple services in waters and airspace around Taiwan, in an apparent response to the ratification of a U.S. defense act that calls for increased security cooperation between Washington and Taipei.

Taiwan's Defense Ministry said Monday seven Chinese warships and 71 military aircraft were detected near the self-ruled democratic island in the 24 hours through 6 a.m., with many warplanes including fighter jets crossing the median line between the mainland and Taiwan, a boundary that had been respected by both sides for decades.

The ministry said the Taiwan military has been closely monitoring the situation and responding to China's unusually large-scale drills.

Photo posted by the People's Liberation Army Eastern Theater Command on its WeChat account on Dec. 25, 2022, shows a bomber upon takeoff. (Kyodo)

The People's Liberation Army Eastern Theater Command said Sunday the firepower striking exercise was "a firm response to the current escalation of provocations" by the United States in collusion with the Taiwan authorities.

Army Senior Col. Shi Yi, the spokesman for the command covering the Taiwan Strait, said it will "take all necessary measures to resolutely safeguard national sovereignty and territorial integrity."

On Friday, U.S. President Joe Biden signed into law an $858 billion defense policy bill, which authorized up to $10 billion in security assistance over the next five years to modernize Taiwan's security capabilities to deter aggression by Beijing.

The legislation also called on the U.S. government to invite Taiwan to participate in a U.S.-led major multinational naval exercise known as RIMPAC in 2024.

On Saturday, the Chinese Foreign Ministry said Beijing "deplores and firmly opposes" the U.S. move, and urged Washington to "stop fudging, distorting and hollowing out the one-China principle."

Mainland China and Taiwan have been governed separately since they split in 1949 due to a civil war. Beijing endeavors to bring the island back into its fold, by force if necessary.

Since U.S. House of Representatives Speaker Nancy Pelosi visited the island in August, China has been increasing its military pressure on Taiwan.

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