The People's Liberation Army (PLA) Eastern Theater Command has been closely tracking U.S. and Canadian warships transiting through the Taiwan Straits, spokesperson Senior Colonel Shi Yi said on Wednesday.

The U.S. Navy's Arleigh Burke-class guided-missile destroyer USS Higgins transited the Taiwan Straits on Tuesday in tandem with the Royal Canadian Navy's Halifax-class frigate HMCS Vancouver.

The theater command remains on high alert to resolutely counter all threats and provocations, and to safeguard national sovereignty and territorial integrity, Shi said.