"Special joint patrol and inspection operation began today in the central and northern parts of the Taiwan Strait," the administration said on Chinese social media WeChat.
The administration also attached an image to the message showing patrol areas, which are located very close to Taiwan.
Following the news, Beijing firmly opposed the meeting as it contradicts the one-China principle and undermines the country's sovereignty, Chinese Foreign Ministry spokeswoman Mao Ning said on Tuesday.
On March 29, the Taiwanese delegation led by Tsai departed for a 10-day trip to two Central American states. On April 1, the delegation arrived in Guatemala with a transit stop in New York and visited Belize on April 3. On Wednesday, the Taiwanese leader will also make a transit stop in Los Angeles on her way home. US media reported that Tsai would hold a meeting with McCarthy during her stay in California that day.
Prior to her meeting with US House Speaker Kevin McCarthy in California, President Tsai Ing-wen met with senior security officials on Tuesday to discuss the "regional situation."
"The president asked relevant units to continue to grasp the surrounding situation, and to enable the visiting delegation to continue to grasp the situation in real time," her office said as quoted by media.
The situation around Taiwan escalated after former US House Speaker Nancy Pelosi traveled to the island in August 2022. Beijing condemned Pelosi's trip, which it regarded as a gesture of support for separatism, and launched large-scale military drills in the vicinity of the island. China's tough reaction notwithstanding, Pelosi's visit unleashed a wave of trips by Western politicians to the island.
Taiwan has been governed independently from mainland China since 1949. Beijing views the island as its province, while Taiwan — a territory with its own elected government — maintains that it is an autonomous country but stops short of declaring independence. Beijing opposes any official contacts of foreign states with Taipei and considers Chinese sovereignty over the island indisputable.