China claims Taiwan is part of its territory and also asserts jurisdiction over the waters around the island, which Taipei rejects.

Taiwan's Coast Guard Administration (CGA) said it dispatched vessels in response to a China Coast Guard announcement that it had carried out another "routine law-enforcement patrol" in waters off Taiwan's east coast.

"The CGA firmly rejects China's cognitive warfare campaign of 'law enforcement in name, jurisdictional expansion in practice'," the Taiwanese coast guard said a statement published on X.

As of 11:00 am (0300 GMT) on Thursday, two Chinese coast guard ships were "loitering and drifting" about 105 nautical miles (195 kilometres) and 74 nautical miles east of Green Island, respectively, the statement said.

"The CGA will continue to take all necessary measures to resolutely safeguard national sovereignty and ensure the security of Taiwan's waters," the coast guard said.

China carried out its first law enforcement patrol east of Taiwan in June.

Beijing has since dialled up pressure, deploying a record 244 coast guard, scientific research and other ships around Taiwan's main island in July, Taiwanese official data show.

That compares with 55 ships detected in June and 30 in May, and 58 in July last year. In the first 21 days of August, 152 vessels were detected.

About 60 percent are coast guard ships, with research vessels and other government boats making up the rest.

The figures do not include Chinese warships, which China's military deploys around Taiwan on a near-daily basis.