Fox reported that Admiral Harry Harris, the head of US Pacific Command, had warned repeatedly about Chinese military build-up in the area over the last year. Satellites have shown China preparing to ship advanced surface-to-air missiles to contested islands, it said.

The US first adoped the “One China” policy in 1972 after meetings between Richard Nixon and Chairman Mao Tse-tsung and it was later solidified by President Jimmy Carter.

Under the policy, the US retains unofficial ties to Taiwan while recognising Beijing as representing China. China considers Taiwan a renegade country.

White House officials said they spoke with the Chinese leadership following Mr Trump’s call with President Tsai.

Federal officials called to reassure the country that the US still adheres to One China, which does not recognise Taiwan as its own sovereign nation.