Taiwan scrambled fighter jets on Friday after a fleet of Chinese military aircraft buzzed the island, stepping up tensions as a senior US official began holding meetings in Taipei.
Beijing had earlier announced the start of combat drills in the Taiwan strait aimed at asserting its claim that the island remained "an inalienable part of China".
The Chinese government has long considered Taiwan a renegade province, although the democratically-governed island has its own president, currency, foreign policy, passport and military.
China has engaged in a bitter war of words and staged multiple drills around Taiwan over recent months to protest growing engagement between the self-ruled island and the US government.
Stronger ties between Taiwan and the US have further weakened Washington’s diplomatic relations with Beijing, which are already at historic lows as the two nations spar over trade, technology, human rights, coronavirus and espionage.
Keith Krach, US undersecretary of state for economic growth, energy and the environment, landed in Taipei on Thursday – the second visit from a senior US official in as many months – a move that has already angered Beijing.
Mr Krach is expected to meet Taiwan president Tsai Ing-wen, participate in an economic dialogue and attend the funeral for former president Lee Teng-hui, known as Taiwan’s "father of democracy".
Before his visit, the US ambassador to the United Nations Kelly Craft met with Taiwan’s top official in New York, James K.J. Lee, the director of the Taipei Economic and Cultural Office. This was the first such meeting since 1971, when the China’s UN seat was passed from Taipei to Beijing.
All this comes as the US is reportedly seeking to sell as many as seven major weapons systems, including mines, cruise missiles and drones, to Taiwan. The move would be a departure from past US policy which spread out the supply of weapons to Taiwan in order to minimise tensions with Beijing.
Under President Donald Trump, Washington has pressured China in many ways, including by blocking components to Chinese companies to prevent them from accessing US technology, banning Chinese social media programs like WeChat over concerns the apps were scraping user data, and sanctioning senior officials responsible for human rights abuses in Xinjiang and Hong Kong.
David Stilwell, US assistant secretary of state for East Asia and the Pacific, called China a “lawless bully” on Thursday in prepared testimony for a congressional hearing.