Taiwan's defence ministry revealed it sent aircraft and ships to "appropriately" react to Chinese training drills on Sunday morning, August 7.
China had been carrying out military training drills around Taiwan for three full days, sparking tension between the two nations.
Some Chinese ships and planes crossed the unofficial border between the two countries over the weekend, Taiwan claimed.
Taiwan premier Su Tseng-chang urged China to not flex its muscles, while accusing it of using the exercises to "arrogantly" disrupt stability in the region.
The defence ministry also said that the Chinese military training drills were a simulated attack on Taiwan.
China's military drills were expected to end on Sunday, after days of tension.
The US also accused China of instigating a dispute, following senior Democrat Nancy Pelosi's visit to Taipei last week.
A White House spokesperson said: "These activities are a significant escalation in China's efforts to change the status quo. They are provocative, irresponsible and raise the risk of miscalculation.
"They are also at odds with our long-standing goal of maintaining peace and stability across the Taiwan Strait, which is what the world expects."
China was furious that Ms Pelosi visited Taiwan, and said the trip "seriously threatened" the peace in the Taiwan Strait.
It also put sanctions on Ms Pelosi and her family, following the state visit.
China and Taiwan had a complicated relationship before the latest tensions.
The Chinese see Taiwan as a breakaway province, and reportedly want to regain its control.
But, Taiwan is an established self-governing country with its own president and cabinet.