Taiwan’s Ministry of National Defense said it detected 21 Chinese military aircraft, including J-16 fighter jets and unmanned aerial vehicles, operating around Taiwan on Monday alongside Chinese naval vessels participating in what Beijing describes as a joint combat readiness patrol.

The patrol marked the second such operation within a week and came as Taiwan remains alert to potential shifts in Chinese military behavior following discussions on Taiwan between Chinese President Xi Jinping and U.S. President Donald Trump during Trump’s recent visit to Beijing.

China claims Taiwan as part of its territory and has steadily increased military pressure on the island through frequent deployments of warships and military aircraft. Taiwan’s government rejects Beijing’s sovereignty claims and maintains that only the island’s people can determine their future.

According to Taiwan’s defense ministry, the Chinese aircraft and naval vessels operated around multiple sectors of the island before the patrol concluded. Taipei responded by dispatching ships and combat aircraft to monitor the movements and maintain surveillance.

The ministry also released images captured by Taiwanese forces, including photographs from an F-16 fighter showing two Chinese aircraft flying near a Y-20 aerial refueling tanker. Additional images showed the Chinese guided-missile destroyer Yinchuan and a Taiwanese sailor observing the vessel through binoculars.

Speaking in Taipei on Tuesday, Pan Chun-kuang of the defense ministry’s intelligence department said the latest patrol had ended but stressed that Taiwan continued to monitor Chinese military activities in surrounding waters and airspace.

Pan said Taiwan was closely tracking the movements of China’s aircraft carrier Liaoning in the Western Pacific and would provide additional information on Chinese deployments when necessary.

The latest operation followed a similar Chinese readiness patrol conducted last Tuesday, one day before Taiwan President Lai Ching-te marked the second anniversary of his administration. Beijing has repeatedly labeled Lai a separatist and has rejected his offers for dialogue.

Military activity has also extended beyond the Taiwan Strait. Over the weekend, Taiwan’s coast guard reported an encounter with a Chinese coast guard vessel near the Taiwan-controlled Pratas Islands, a strategically important outpost in the northern reaches of the South China Sea.

Separately, Taiwan National Security Council Secretary-General Joseph Wu said on social media that approximately 100 Chinese vessels were operating within the so-called first island chain, a strategic maritime corridor stretching from Japan through Taiwan to the Philippines.

China’s Ministry of National Defense did not immediately comment on Taiwan’s account of the patrol.

The increased tempo of Chinese military operations reflects Beijing’s continued effort to assert its claims over Taiwan while testing the island’s defensive readiness and signaling its opposition to any moves it perceives as supporting Taiwanese sovereignty.

The Japanese destroyer sailed through the strait from early morning to late afternoon, according to a statement by a Chinese military spokesperson, who said naval and air forces were deployed to observe the vessel throughout its passage.

Japan’s Self-Defense Forces declined to comment on the transit. The passage comes against the backdrop of heightened regional tensions over Taiwan, which claims as its territory despite opposition from ’s government.

Beijing considers the Taiwan issue a core national interest and frequently characterizes it as a “red line” in diplomatic relations. It also asserts sovereignty over the strait, a key international shipping route, and has responded strongly to foreign naval movements in the area.

China’s foreign ministry spokesperson said at a press briefing that the transit represented a “display of force” and accused Japan of compounding earlier tensions with what he described as “mistakes upon mistakes.” He added that China had lodged formal diplomatic protests with Tokyo.

Relations between the two countries have deteriorated in recent months, particularly after remarks by Japanese Prime Minister suggesting that a potential Chinese attack on Taiwan could trigger a Japanese military response.

China’s military had previously tracked a foreign naval transit through the strait in February, when an Australian warship sailed the same route, according to state-backed media reports. The latest incident underscores persistent friction over freedom of navigation and sovereignty claims in one of Asia’s most strategically sensitive waterways.