Taiwan has spotted two Chinese warships operating in waters near the Penghu islands in the Taiwan Strait and has sent its own naval and air forces to keep watch, the defence ministry in Taipei said.
China, which views democratically governed Taiwan as its own territory, sends its warships and warplanes into the waters and skies around the island on an almost daily basis, to the condemnation of the Taiwanese Government.
While Taiwan's defence ministry offers daily updates of the locations of Chinese military aircraft, it only rarely gives details of where Chinese warships are operating, generally only when it detects aircraft carriers, as happened last week.
Late Monday, the ministry said a Chinese destroyer and a frigate had entered waters to the south-west of the Penghu islands, home to major Taiwanese navy and air bases and close to the Taiwan side of the strait.
Taiwan's military, "closely monitored the formation and responded appropriately using naval and air forces", the ministry added, without elaborating.
The ministry showed colour pictures of both ships taken from the air, but did not give an exact location.
China's defence ministry did not immediately respond to a request for comment. Earlier this month, it said China's regular military activities around Taiwan are, "entirely justified and reasonable," and any tensions are the fault of the government in Taipei.
Speaking to Coast Guard officers in Taipei on Tuesday, Taiwanese President Lai Ching-te said China's "grey-zone" operations — irregular tactics to exhaust a foe without resorting to open combat — and psychological pressure have grown day by day.
"They seek to manufacture a new normal that undermines the status quo," he added.
On Tuesday morning, in its daily update of Chinese activities over the past 24 hours, Taiwan's defence ministry said a total of nine Chinese warships were operating around the island, with 22 military aircraft detected.
While it showed a map of where the Chinese aircraft were, mostly in the strait and to the north and south-west of Taiwan, it did not provide any other information about the location of the warships.
Taiwan's Coast Guard is on the front lines of monitoring Chinese activities in an auxiliary role to the navy and Lai said its abilities would be strengthened.
That includes integrated sea-and-air surveillance capabilities, with an expanded deployment of drones, next-generation radar systems and infrared thermal imaging systems, Lai said.
Taiwan's government rejects Beijing's sovereignty claims, saying only the island's people can decide their future.
(Reporting by Ben Blanchard; Editing by Lincoln Feast and Thomas Derpinghaus)