Taiwan's President Lai Ching-te thanked troops on Tuesday after China held military exercises around the self-ruled island, as he urged them to help make it "safer".

Three days after Lai was sworn into office, warships and fighter jets encircled Taiwan in drills China said were a test of its ability to seize the island it claims as part of its territory.

Lai vowed in his inaugural speech to defend Taiwan's democracy and freedom, which Beijing said amounted to a "confession of independence".

Speaking during a visit to an air force base in eastern Hualien on Tuesday, Lai toasted the troops for their hard work "in response to China's military exercises" -- his first direct reference to the war games on Thursday and Friday.

"Let's work together and continue to work hard to make our country safer," he said.

"Everyone is on standby 24 hours a day to perform air patrol missions... All brothers and sisters use their firm determination and outstanding combat skills to demonstrate their air combat capabilities and protect our airspace," he added.

Lai also visited an army base where he watched artillerymen demonstrate loading and discharging a howitzer.

He gave the soldiers a "red envelope" -- a tradition during holidays -- as a token of appreciation and took group photos with the troops.

The Hualien air force base saw dozens of fighter jets take off on Friday, the second day of China's military drills.

China has upped military and political pressures on Taiwan in recent years, and its naval vessels, drones and warplanes maintain a near-daily presence around the island.

On Tuesday, Taiwan's defence ministry said three Chinese warplanes, and 11 naval and coastguard ships were detected in the past 24 hours -- down from the 21 aircraft and 15 ships it reported on Monday.

Experts say these are "grey zone tactics", which stop short of outright acts of war but serve to exhaust Taipei's military.