China’s Coast Guard said the patrol would carry out what it described as “law enforcement patrols” in waters it considers under its jurisdiction. In a statement, the agency said it would strengthen such operations to safeguard what it called China’s territorial sovereignty and maritime rights and interests.

The move marks the second deployment in roughly a month of Chinese coast guard vessels to waters off Taiwan’s eastern coast. Unlike the near-daily military activities conducted by the People’s Liberation Army around Taiwan, Beijing has increasingly relied on coast guard vessels to reinforce its territorial claims, a strategy Taiwanese officials describe as “lawfare” aimed at creating a legal basis for Chinese actions.

Taiwan’s Mainland Affairs Council rejected Beijing’s claims, saying China has neither sovereignty nor jurisdiction over waters east of Taiwan and that its coast guard has no law enforcement authority in the area. The council described the patrol as an illegal expansion of power that violates international law and undermines regional peace and stability.

Taiwan’s Coast Guard Administration said it was monitoring two Chinese coast guard vessels involved in the operation and had dispatched two Taiwanese ships to shadow them. By mid-morning, the Chinese vessels were about 54 nautical miles east of Hualien, home to one of Taiwan’s major air bases, but remained outside Taiwan’s restricted waters.

The coast guard said it would continue taking all necessary measures to monitor Chinese vessels and respond to any activities it considers harassment, while safeguarding Taiwan’s maritime security and sovereignty.

The latest operation follows a similar patrol conducted by China in June, which drew concern from the United States and several European partners, including France, Germany and Britain. Beijing said that deployment was a response to Japan and the Philippines announcing formal discussions on maritime boundaries, which China argued involved waters connected to its claims around Taiwan.

Earlier this week, Taiwan instructed commercial and civilian vessels operating off its eastern coast to refuse any boarding or inspection requests by the Chinese Coast Guard. Authorities said Taiwanese coast guard ships would intervene if necessary to prevent such actions.

The dispute reflects broader tensions across the Taiwan Strait, where China continues to increase military and coast guard activities while maintaining that Taiwan is part of its territory. Taiwan, which is democratically governed, rejects Beijing’s sovereignty claims and insists only its own government has the authority to exercise jurisdiction over the island and its surrounding waters.

On Thursday, China’s Ministry of Natural Resources published an English-language legal opinion criticizing maritime boundary discussions between Japan and the Philippines. The ministry argued that any negotiations involving waters claimed by Beijing should include China rather than Taiwan and called on other countries not to support the bilateral talks.

The latest coast guard deployment is likely to add to regional tensions as China continues to expand the use of civilian maritime agencies alongside military operations to advance its territorial claims in the western Pacific.

The Immediate Combat Readiness Exercises, announced by Taiwan’s Ministry of National Defense on Sunday, focus on assessing how quickly military units can mobilize and respond to potential threats, particularly in scenarios involving sudden escalation short of open conflict.

In Taoyuan, home to Taiwan’s largest international airport and a strategically important transportation hub, tanks and armored vehicles from the Army’s 269th Infantry Brigade were deployed on city streets and highways as part of combat readiness patrols, according to images and footage released by military authorities.

Taiwan’s defense ministry said the drills emphasize realistic operational conditions, including live-fire elements and real-time decision-making. The exercises are intended to simulate military responses during the critical period preceding a potential hostile assault.

According to Taiwan’s semi-official Central News Agency, the drills are structured to evaluate the military’s ability to react swiftly before an adversary launches amphibious or air operations. Authorities indicated that additional unscheduled exercises could be conducted in the future to test immediate responses to evolving security situations.

The drills come amid continued military activity by China around Taiwan. Taiwan’s defense ministry reported that 23 Chinese military aircraft, seven naval vessels and five government-operated ships were detected operating near the island between Sunday and Monday.

China regularly deploys warplanes, naval vessels and drones near Taiwan in what Taipei describes as pressure tactics intended to wear down the island’s defenses and signal Beijing’s territorial claims.

Grey-zone operations, which have become a central feature of cross-strait tensions, encompass activities such as military patrols, air incursions, maritime presence and drone operations that fall below the threshold of direct armed conflict but are designed to exert strategic pressure.

Beijing considers Taiwan part of its territory and has repeatedly stated that reunification remains a national objective. Chinese authorities have not ruled out the use of force to achieve that goal.

Taiwan, which operates as a self-governing democracy, has increasingly focused on strengthening its defense posture through expanded training programs, weapons modernization and civil defense preparations. Earlier this month, Taiwanese forces conducted a military exercise that included firing rockets toward waters facing China, marking a notable demonstration of defensive capabilities.

The latest readiness drills underscore Taipei’s efforts to improve rapid-response capabilities as military activity around the Taiwan Strait continues to intensify.

China’s parliament, the National People’s Congress, approved the legislation on Thursday, aiming to foster a shared national identity among China’s 55 officially recognised ethnic minority groups, including Tibetans and Uyghurs.

While the law does not explicitly mention Taiwan, Beijing considers the island part of its territory and regards its people as Chinese citizens.

Shen Yu-chung, deputy minister at Taiwan’s Mainland Affairs Council, said language in the legislation could potentially extend to cross-strait issues.

Speaking to reporters in Taipei before the law was formally passed, Shen said provisions requiring citizens to protect China’s sovereignty and national unity could “spill over into becoming a legal basis for handling cross-Strait issues.

”When asked whether the law might be used to target individuals Beijing views as pro-independence activists, Shen said it was “highly possible,” adding that the definition of promoting unity remained vague while penalties could be more clearly defined.

China, which views democratically governed Taiwan as its own territory, has already introduced measures aimed at supporters of Taiwanese independence.In 2024, Chinese authorities issued guidelines to punish what they called “diehard” independence activists, with penalties that could include the death sentence, despite Chinese courts having no jurisdiction on the island.

The new legislation also contains a brief reference encouraging people on both sides of the Taiwan Strait to identify as Chinese.

The law further cites remarks by Chinese President Xi Jinping stating that citizens must “consciously uphold national unity, national security, and social stability.”

Taiwanese officials have long criticised what they describe as Chinese “lawfare,” referring to the use of legislation to create legal grounds for targeting individuals Beijing considers separatists, including those living overseas.

The new law includes provisions stating that individuals and organisations outside the borders of the People’s Republic of China can be held legally accountable for undermining ethnic unity or inciting separatism.

Shen said such language raised concerns about potential “long-arm jurisdiction,” referring to China’s efforts to apply its legal framework beyond its borders.

China’s Taiwan Affairs Office did not respond to a request for comment.