Less than a week before the self-ruled island of Taiwan installs its new president, whom China views as a "dangerous separatist," Taipei announced on Wednesday that it had discovered 45 Chinese military aircraft in the area. This is the highest number of aircraft detected in one day this year.

China has declared that it will never give up using force to annex democratic Taiwan and claims it as part of its territory.

Tensions have increased since Lai Ching-te won the January election because of threats that the island would see "war and decline" under his leadership as vice president, who will be sworn in on May 20.

On Wednesday, the defense ministry in Taipei announced that it had seen six naval vessels and 45 Chinese aircraft cruising around Taiwan twenty-four hours before 6:00 am (2200 GMT).

"26 of the aircraft crossed the median line of the Taiwan Strait," the ministry said in a statement, referring to a line bisecting the 180-kilometre (110-mile) waterway that separates Taiwan from China.

The ministry said it had "monitored the situation and responded accordingly."

The ministry reported on Tuesday night that over two hours, 23 Chinese aircraft, including fighter jets and drones, had been spotted in the Taiwan area.

Beijing has increased its military presence in Taiwan in recent years, deploying warplanes, drones, and naval vessels almost nonstop throughout the island.

When Beijing dispatched 103 warplanes and aircraft to Taiwan last September, 40 crossed the median line, making it the largest ever seen in the area.

According to experts, these are "grey zone tactics" that wear out Taipei's military without going so far as full-scale acts of war.

China has been deploying coast guard ships and official fishing vessels around Taiwan's outlying island of Kinmen since February, in addition to displaying military might.

Taiwan's coast guard reported that the most recent sighting occurred on Tuesday, when five Chinese coast guard ships passed through Kinmen's "restricted waters" for three hours before sailing away.

The Taiwanese Coast Guard stated that the formations "seriously affect navigation safety and undermine peace and stability across the Taiwan Strait" and that Tuesday's sighting was the fifth one observed in May.

"We urge the Chinese side to exercise self-restraint and immediately cease this irrational behaviour," it said.

Like outgoing President Tsai Ing-wen, Lai rejects Beijing's claim over Taiwan.

China has condemned him and his deputy Hsiao Bi-khim- Taiwan's former representative to the United States- as an "independence duo".