Taiwan has urged China to release a fishing boat with five crew members, allegedly seized by the Chinese coast guard near Taiwan's outlying islands.

In response to a series of deadly fishing incidents, including one that resulted in sharp exchanges of blame, the Chinese coast guard has increased its patrols around Taiwan's Kinmen islands in recent months.

The Kinmen islands, administered by Taipei but situated just five kilometers (three miles) from the Chinese mainland, have been the focus of recent tensions.

Taiwan's coast guard reported that at 8:14 pm (1214 GMT) on Tuesday, the owner of a fishing boat notified them that two Chinese coast guard vessels had intercepted the boat approximately 23.7 nautical miles (44 kilometers) from Kinmen's Liaoluo port.

Taiwan's coast guard dispatched two patrol vessels to attempt a rescue, along with a third for support. However, one of the patrol vessels was "blocked by" Chinese coast guard ships, according to a statement released on Tuesday night.

"We broadcast to the Chinese coast guard ship, demanding the immediate release of our fishing boat. The Chinese side also broadcast to us, asking not to interfere," it said.

"To avoid escalating the conflict, we have decided to stop the chase," the coast guard said, claiming that the fishing boat was taken to China's Weitou port.

During a news conference on Wednesday, Taiwanese coast guard officials said that the seized boat had two Taiwanese and three Indonesian crew members onboard. Deputy Coast Guard Chief Hsieh Ching-chin claimed that the boat was taken near China's Jinjiang City, an area where Beijing has enforced a "fishing moratorium" from May 1 to August 15.

"We hope that the Chinese side will tell us as soon as possible for the reason of the inspection," he said.

It is worth noting that new maritime rules issued by China on June 15 allow the China Coast Guard to detain foreigners for trespassing in Chinese-claimed territories in the South China Sea.

These regulations have sparked outrage in the region, as governments closely allied with the United States, such as those in the Philippines and Taiwan, see the new regulation as threatening. 

Inevitable reunification

Beijing has repeatedly affirmed its position that Taiwan belongs to mainland China, citing historical context, and has constantly affirmed its opposition to Washington's increasingly hostile policies in the South China Sea and its encroaching on its geopolitical sphere, particularly regarding the island.

In his New Year's address last December, Chinese President Xi Jinping adamantly declared the reunification of Taiwan inevitable.

"Compatriots on both sides of the Taiwan Strait should be bound by a common sense of purpose and share in the glory of the rejuvenation of the Chinese nation," he said then.

This came shortly after Xi Jinping told US President Joe Biden in a November summit in San Francisco that China will ultimately reunify with Taiwan, albeit on an undetermined timeline.

Meanwhile, the United States has repeatedly claimed it adhered to the One China policy, which is a nonnegotiable prerequisite to any diplomatic relations with Beijing. While Washington has no official diplomatic ties with the island, it has signed a series of military and arms agreements, all explicitly directed against China.

The Taiwan Relations Act, signed in 1979, commits the United States to supply weapons to the island and any services it needs to "defend itself from China." However, Washington remains extremely vague over whether it would directly join Taiwan in any war with China or would assume a less involved role.

Biden has repeatedly said the United States would "defend Taiwan", but US officials have claimed there is no change to the American official policy.

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