Read more: Tsai Ing-wen, Taiwan's shy but steely leader

From concern to alarm and anger - Carrie Gracie, BBC China editor, Beijing

Image copyright Reuters Image caption In an image released by her office, Taiwan's President Tsai Ing-wen is seen speaking on the phone to Mr Trump

Mr Trump's decision to turn his back on four decades of US protocol on Taiwan and speak directly to a president of Taiwan has stunned policymakers in Beijing. The 10-minute telephone call with Taiwan’s leadership was the first by a U.S. president-elect or president since President Jimmy Carter switched diplomatic recognition from Taiwan to China in 1979, acknowledging Taiwan as part of “one China.”

China’s Foreign Ministry said it had lodged “stern representations” with what it called the “relevant U.S. side,” urging the careful handling of the Taiwan issue to avoid any unnecessary disturbances in ties. Even without Trump’s full foreign policy team in place, he had more phone calls with foreign leaders Friday, breaking tradition by speaking with Taiwanese President Tsai Ing-wen, a transition team spokeswoman said, in a move likely to infuriate China and expected to complicate relations. President-elect Trump also congratulated President Tsai on becoming President of Taiwan earlier this year,” a release from the presidential transition team said on Friday afternoon, setting off alarm bells in many capitals. The transition team later issued a statement saying that the two had noted that “close economic, political and security ties exist between Taiwan and the United States.”

An official of Taiwan’s representative office in Washington could not confirm the call but said it would be “historic” and the first contact between U.S. and Taiwanese leaders since diplomatic ties were severed in 1979 and Washington established official ties with Beijing.
The People's Republic of China lodges a complaint with the United States after President-elect of the United States Donald Trump speaks with President of Taiwan Tsai Ing-wen. The PRC and the United States view Taiwan as a breakaway province.