PLA Eastern Theatre Command spokesman Senior Colonel Shi Yi said they were exercises to “seize maritime and airspace control” while testing “the capability of the command’s forces in coordinated operations and systematic confrontation”. They were conducted to the north and southwest of the island.

Lin Ying-yu, a professor of international relations and strategic studies at Tamkang University in New Taipei City, said Beijing had to “do something in response to Lai’s US stopovers”.

“If they didn’t do anything, it would mean they had tacitly agreed or consented to Lai’s trip,” Lin said.

He noted that the PLA had conducted the drills a day after the US, Japanese and South Korean leaders reaffirmed their commitment to maintaining peace and stability across the Taiwan Strait following a summit on Friday.

Max Lo, executive director of the Taiwan International Strategic Study Society, a Taipei think tank, said the latest PLA drills were more restrained than the last two rounds.

“Apparently the mainland authorities conducted the drills in line with the principle of proportionality, as both the days and scale of the last two rounds were much longer and bigger,” he said.

Lai’s US stopovers were more low-profile than when Tsai visited and comparatively less provocative than the president’s, according to Lo.

Tsai transited through the US in late March and early April on her way to visit Central American allies Guatemala and Belize. Tsai met a number of senior US officials and congressmen during her stopovers.

Beijing views Taiwan as its territory and has not renounced the use of force to bring the island under its control. It saw Washington’s permission for the Taiwanese leaders’ US transits as a breach of the one-China policy, and their official contacts as a violation of its sovereignty.

The US, like most countries, does not recognise Taiwan as an independent state, but is opposed to any unilateral change to the status quo by force.

After Lai’s visit, between 6am Saturday and 6am Sunday, the PLA sent 45 warplanes and nine warships for operations around the island, according to Taiwan’s defence ministry. Twenty-five of the warplanes were said to have crossed the de facto median line dividing the Taiwan Strait.

But from 6am Sunday to 6am Monday, only two PLA aircraft and six vessels were detected around Taiwan, none of which crossed the median line.

The drills were played up on state television in mainland China. Broadcaster CCTV aired footage of the exercises on Saturday, saying they involved destroyers, corvettes, missile boats, fighter jets, air warning systems and rocket forces in a simulated encirclement of the island.

A map of Taiwan was shown with three slogans superimposed on it: “Relying on the US is an evil road”, “Seeking independence is a dead end”, and “Reunification is the right road”.

The PLA released another video clip via Chinese media on Monday portraying its troops as protectors of the Taiwan Strait – likening them to the Goddess of Matsu who offers assistance to seafarers.

Taiwan’s defence ministry responded with two video clips. One featured Taiwanese sailors on the guided-missile frigate Tian Dan shadowing the PLA’s Xuzhou frigate. The other showed Taiwanese worshippers of Matsu during a pilgrimage, calling for peaceful protectors rather than warmongers from mainland China.

Singapore-based defence analyst Alexander Neill told Reuters it appeared that Beijing had calibrated the scale of the drills to make a point without upsetting broader diplomatic efforts.

“I think after recent bilateral engagement China probably doesn’t want to rock the boat too much before Apec in San Francisco,” Neill, an adjunct fellow of Hawaii’s Pacific Forum think tank, said, referring to November’s Asia-Pacific Economic Cooperation summit.