China was furious when two U.S. Navy vessels sailed this week through the Taiwan Strait, the first time since Donald Trump assumed office in late January.

About once a week, the U.S. Navy transits the Strait, sometimes accompanied by ships of allied nations. China, which claims Taiwan to be its territory, claims the strategic waterway as theirs.

The US Navy confirmed that the ships were the guided-missile destroyer USS Ralph Johnson of the Arleigh Burke class and the survey ship USNS Bowditch, both of the Pathfinder class. It said that the ships made a transit from north to south between February 10-12.

"The transit took place through a narrow corridor that runs along the Taiwan Strait, beyond the territorial waters of any state on the coast," explained Navy Commander Matthew Comer. He is a spokesperson for the U.S. Indo-Pacific Command. "Within this area, all nations have high seas freedom of overflight and navigation. They also enjoy other international lawful uses of the ocean related to these freedoms."

China's military has said that Chinese troops have been sent to keep watch.

The Eastern Theatre Command of the People's Liberation Army issued a statement in the early hours of Wednesday.

Taiwan's Defence Ministry said that its forces also remained on the alert but stated that "the situation was normal".

The last U.S. Navy missions in the strait were in late November when a P-8A Poseidon patrol aircraft flew above the waterway.

Last time an American Navy ship was confirmed as having sailed the Strait, it was in October. It was a joint mission between a Canadian warship and a U.S. Navy vessel.

China's military is active in the Taiwan Strait every day, as part what Taiwan's Government views as Beijing's pressure campaigns.

Taiwan's Defence Ministry said on Wednesday that it detected 30 Chinese military aircrafts and seven navy vessels operating around the island.

Taiwan President Lai Ching Te rejects Beijing's claims of sovereignty, saying that only Taiwanese people can decide the future. Reporting by Liz Lee and Ben Blanchard, in Beijing; Additional reporting and editing by Phil Stewart and Idrees in Washington.

(source: Reuters)