China insists democratic, self-ruled Taiwan is part of its territory and has threatened to use force to bring the island under its control.

Beijing has ramped up the deployment of fighter jets and naval vessels around Taiwan in recent years to press its claim of sovereignty, which Taipei rejects.

Taiwan also accuses China of using espionage, cyberattacks and disinformation to weaken its defences.

Along with the 50 aircraft, six Chinese naval vessels were also detected in the 24 hours to 6:00 am (2200 GMT Thursday), the defence ministry said.

It said in a separate statement that an additional 24 Chinese aircraft including fighters and drones were spotted since 08:50 am Friday.

Among them, 15 crossed the median line of the Taiwan Strait in conducting air-sea joint training with Chinese naval vessels, the ministry said, adding it "monitored the situation and responded accordingly".

The latest incursion came after British Royal Navy patrol vessel HMS Spey sailed through the Taiwan Strait on June 18, Taiwan's foreign ministry said Thursday.

The United States and other countries view the 180-kilometre (112-mile) Taiwan Strait as international waters that should be open to all vessels.

The last time a British Navy ship transited the Taiwan Strait was in 2021, when the HMS Richmond, a frigate deployed with Britain's aircraft carrier strike group, sailed through from Japan to Vietnam.

China strongly condemned Britain at the time and deployed its military to follow the vessel.

In April, Taiwan detected 76 Chinese aircraft and 15 naval vessels around the island, when Beijing conducted live-fire exercises that included simulated strikes aimed at the island's key ports and energy sites.

The highest number of Chinese aircraft recorded was 153 on October 15, after China staged large-scale military drills in response to Taiwan's President Lai Ching-te's National Day speech days earlier.