China says it is "ready to defeat any provocation" as two US Navy warships sail through international waters in the Taiwan Strait.
It comes just weeks after US House Speaker Nancy Pelosi visited the region - the highest-ranking elected US official to visit in more than 25 years.
Mrs Pelosi's visit angered China, which regards Taiwan as a renegade province to be annexed by force if necessary.
The US Navy said the cruisers Chancellorsville and Antietam had "transited through a corridor in the strait that is beyond the territorial sea of any coastal state".
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The operation demonstrates the US commitment to a free and open Indo-Pacific, and the US military flies, sails and operates anywhere international law allows, the navy added.
Nations including the UK and Canada have been among the other nations to send ships through the Taiwan Strait in recent years.
China's military said it was monitoring the US naval movements, ready to "defeat any provocation".
Taiwan's defence ministry said the two US ships were sailing in a southerly direction and that its forces were observing, but that "the situation was as normal".