China has sparked alarm by staging "strike drills" simulating an attack on Taiwan as tensions rise.
Beijing confirmed it had carried out the air and sea drills at an unspecified location, vowing to defend "territorial integrity".
It claimed it had been motivated by provocation by the US - just 24 hours after hitting out at US military assistance for Taiwan.
It marks a further escalation in tensions between the two superpowers after the passing of new legislation - the US National Defense Authorization Act - which approved $10 billion in assistance and weapons support for Taiwan.
In a statement the Eastern Theater Command of the People's Liberation Army said it had carried out "joint combat readiness patrols and joint firepower strike drills".
The statement continued: "We will take all necessary steps to defend sovereignty, territorial integrity."
It comes as tensions mount between the US and China over Taiwan, which Beijing considers part of its own territory.
Lashing out US support for Taiwan, the Chinese foreign ministry said yesterday: "The case ignores the facts to exaggerate a 'China threat', wantonly interferes in China's internal affairs and attacks and smears the Chinese Communist Party, which are serious political provocations to China."
It claimed the US legislation "severely affects peace and stability across the Taiwan Strait".
Taiwan had previously welcomed the US legislation - signed by President Joe Biden on Friday - praising Congress "for showing the great importance it attaches to Taiwan-U.S. relations and strengthening Taiwan's security".
Taiwan - which has a population of 23 million - does not accept Chinese rule.
Tensions have been high since the summer, when China staged war games close to Taiwan following a visit to the island by US Speaker Nancy Pelosi.
