By Simone McCarthy, Nectar Gan and Eric Cheung, CNN

Hong Kong/Taipei (CNN) — The Chinese military said Tuesday it had launched joint exercises involving its army, navy, air force and rocket force around Taiwan as a “stern warning,” days after US defense chief Pete Hegseth vowed to counter “China’s aggression” on his first visit to Asia.

China’s armed forces will “close in” on the self-governing island from “multiple directions” in the drills and practice maneuvers including “assault on maritime and ground targets” and “blockade on key areas and sea lanes” to test joint operations capabilities of the troops, the People’s Liberation Army (PLA)’s Eastern Theater Command said in a statement on social media.

“It is a stern warning and forceful deterrence against ‘Taiwan Independence’ separatist forces, and it is a legitimate and necessary action to safeguard China’s sovereignty and national unity,” the statement added.

China’s latest military exercises come as Taiwan is looking on nervously as US President Donald Trump transforms Washington’s global relationships with his mercantilist “America First” foreign policy, discarding decades-old guarantees towards Europe and pushing long-standing Asian allies and partners to pay more for US protection.

Meanwhile, officials close to Trump have repeatedly emphasized the need for the US to focus its attention and resources on countering China’s ambitions in the Indo-Pacific.

For Taiwan, a democracy of some 23 million people that sits just 80 miles from China at its nearest point, the drills are the latest reminder of the threat that comes from its giant Communist Party-run neighbor, which claims the island as its own and has vowed to seize it by force if necessary.

Taiwan officials have condemned the drills as “reckless” and “irresponsible.”

“It came without justification, violates international laws and is totally unacceptable. Democracies need to condemn China for being a troublemaker,” Joseph Wu, secretary-general of Taiwan’s National Security Council, said in a post on social platform X.

The Taiwanese Defense Ministry said it detected 71 Chinese military aircraft and 13 PLA navy vessels near Taiwan, as well as a group of warships led by China’s first domestically built aircraft carrier, the Shandong, in the West Pacific.

The ministry added that its troops are on “high vigilance” to respond to the situation.

Taiwan’s military dispatched its own aircraft and ships, and deployed land-based missile systems to closely monitor the situation and respond appropriately, the island’s Defense Ministry said in a statement about the Shandong aircraft carrier group.

The Eastern Theater Command released a video of the PLA taking part in the drills on Tuesday, showing Chinese frigates sailing, military aircraft taking off and missiles being erected into launch position.

Later in the day, it said it organized naval and air force formations to conduct exercises in the northern, southern and eastern waters surrounding Taiwan, in coordination with conventional missiles and long-range rocket artillery. It did not say how long the exercises would last.

Hegseth’s Asia trip

In Taiwan, government officials and experts view the Chinese drills as a signal to the Trump administration, where several key cabinet officials are hawkish on China, in particular Hegseth and Secretary of State Marco Rubio.

During his first trip to Asia as US defense secretary last week, Hegseth vowed to enhance America’s military alliance with the Philippines to “reestablish deterrence” to counter “China’s aggression” in the Indo-Pacific region, and called Japan an “indispensable partner in deterring communist Chinese military aggression,” including across the Taiwan Strait.

An internal analysis by the Taiwan government cited Hegseth’s visit as among the “external reasons” for China’s latest drills.

“They have reaffirmed the importance of security and stability in the Taiwan Strait, and confirmed that the US is shifting its security focus to the Indo-Pacific region. This has put great pressure on Beijing’s intentions,” according to the analysis, shared with CNN by a senior Taiwanese national security official.

“Faced with upcoming US-China trade talks and the expected measures against China, Beijing has opted for restraint to avoid actions that could be seen as directly confronting the US. Taiwan serves as the perfect pretext, prompting Beijing to launch these military drills immediately after the US Secretary of Defense left Asia,” the analysis added.

Su Tzu-yun, a director at the Institute for National Defense Security Research in Taiwan, said unlike the two “Joint Sword-2024” military drills China conducted last year, the latest exercises came as a “surprise” on Tuesday morning.

“I think Beijing is trying to show its signal to Washington,” Su said.

On Tuesday, China’s coast guard said it also launched “law-enforcement patrols” in waters surrounding Taiwan, carrying out drills including interception and detention of “unwarranted vessels.”

Rising tensions

The Chinese military has ramped up regular patrols as well as military exercises in the air and waters around Taiwan, part of a broader assertiveness of China’s territorial claims under Chinese leader Xi Jinping.

Major exercises often serve as means for Beijing to express displeasure with the island – as well as to better understand how Taiwan monitors and responds to military pressure from China.

China’s military has in recent years launched drills encircling Taiwan and simulating a blockade of the island – one of the strategies that experts say could be used if Beijing ultimately decides to move to take control using military might.

Zhang Chi, a professor at the PLA’s National Defense University in Beijing, said Tuesday’s drills don’t have a specific codename because such military exercises have increasingly become routine.

“This largely indicates that the exercises we see today have become a new normal for the PLA and the Eastern Theater Command – it’s routine for them,” he told China’s state broadcaster CCTV.

Beijing has repeatedly accused Taiwan’s leaders of seeking “independence,” and views Taiwan’s President Lai Ching-te as a “separatist,” launching large-scale drills days after Lai’s inauguration last year.

On Tuesday, the PLA’s Eastern Theater Command released a series of propaganda videos after announcing the latest drills, including one that depicts Lai as a green cartoon bug and calls him a “parasite” hollowing out the island.

Zhu Fenglian, a spokesperson for China’s Taiwan Affairs Office, called the military exercises “a resolute warning to the Lai Ching-te administration’s rampant provocations for ‘independence.’”

Lai, who has long been a champion of Taiwan’s sovereignty, has called on China to cease its intimidation, but he has also spoken frequently of the importance of maintaining “peace and stability in the Taiwan Strait.”

Polls consistently show people in Taiwan, a thriving and outspoken democracy, have no desire to be ruled by China, an authoritarian one-party state.

The latest drills follow a series of incidents that have ratcheted up tensions across the Taiwan Strait, including Taipei’s detention in late February of a cargo ship crewed by Chinese nationals it was investigating for allegedly cutting an undersea internet cable in the second such incident in a period of months.

Last month, Lai called China a “foreign hostile force” and ramped up national security measures to combat Chinese espionage and infiltration. Days later, Taiwan deported a Chinese influencer for backing a military takeover of the island democracy by Beijing.

Taiwan has long been seen as a potential flashpoint that could spark hot conflict between China and the United States.

The US maintains unofficial relations with Taipei and is bound by law to provide Taiwan with weapons for its defense. Washington has long maintained a policy of strategic ambiguity on whether it would come to Taiwan’s defense in the event of an incursion from China.