Taiwan has reported a sharp increase in activity by Chinese coast guard and research vessels around the island in June. This has forced Taipei to plan exercises simulating an escalation of China's actions off the island's Pacific coast, according to data from the Taiwanese coast guard, Reuters reports.
According to data, 55 Chinese government vessels, including coast guard ships and research vessels, were detected around Taiwan in June, compared to 30 in May.
This is an increase of 83% compared to May and a growth of 120% compared to the 25 similar detections in June last year. The statistics do not include ships around Taiwan-controlled islands off the Chinese coast.
The data underscores the growing role of the Chinese coast guard in Beijing's latest campaign to pressure Taiwan - actions that have angered Taipei and alarmed a number of Western countries, including the United States, Britain, France and Germany.
China's armed forces conduct almost daily operations around Taiwan, but in recent years Beijing has increasingly used its coast guard to assert its territorial claims through what Taipei calls a "legal war" - attempts to create a legal basis for Chinese actions around the island.
Taiwanese officials said the activity showed a serious risk in the event of a military conflict - that Beijing could be rehearsing how to cut off Taiwan's Pacific supply lines from its allies.
"If the situation escalates to a blockade - or to something that would effectively be a near-war - we have plans together with the navy to protect Taiwan's vital sea routes," a senior Taiwanese coast guard official said during a briefing.
"We are preparing for such a scenario not only through staff simulations but also through real-life exercises," he added.
China does not recognize Taiwan's sovereignty and insists that the democratically ruled island is part of Chinese territory. Taipei counters that Beijing has no right to claim sovereignty or jurisdiction over the island and its surrounding waters, and that only the Taiwanese people have the right to decide their own future.
The ruling Democratic Progressive Party (DPP) has consistently defended Taiwan's separate identity from China.
Another senior Taiwanese coast guard official said that some of the Chinese coast guard ships are converted former naval destroyers that have been repainted and incorporated into the coast guard. Because of their large size, long range and military capabilities, these ships pose a significantly greater threat to the Taiwanese coast guard.
He said Chinese coast guard ships now often operate in pairs just outside Taiwan's exclusive economic zone in the Pacific Ocean - a vast area that puts a serious strain on Taiwan's limited coast guard fleet.
"This is seriously testing the capabilities of Taiwan's coast guard ships," he noted.
Another senior Taiwanese official described China's actions as "expansion" and an attempt to change the status quo.
Taiwanese authorities say the Chinese coast guard has begun radioing merchant ships, requesting information about the ports they enter and leave. In this way, Beijing is putting pressure on commercial shipping, although so far no ship has changed course.
Taiwanese authorities, for their part, have instructed commercial ships by radio to continue their normal sailing and to ignore Chinese interference.
"China knows that there is currently no jurisdiction there, so it is trying to create one out of thin air," said the second official, who also wished to remain anonymous.