The U.S. government on Tuesday held a dedication ceremony for Washington's new de facto embassy in Taiwan, with which it maintains substantial but non-official ties.
Joining Moy was U.S. Assistant Secretary of State for Educational and Cultural Affairs Marie Royce, who called the new office "a symbol of the strength and vibrancy of the U.S. -Taiwan partnership in the 21st century".
Trump decided not to send cabinet-level officials to the opening ceremony to avoid further antagonising Beijing amid other tensions over trade and China's claims to much of the South China Sea, sources with ties to the United States and Chinese governments told the South China Morning Post earlier this month. "The Trump Administration has been slow to fill key posts in the State Department, which is bad for USA allies in East Asia, Taiwan included".
"The United States sending officials to Taiwan under any excuses is in serious violation of the "one China" principle," Geng Shuang, a Chinese Foreign Ministry spokesman, said during a daily news briefing.
Taiwan's president, Tsai Ing-wen, several Taiwanese government officials as well as legislators were also present.
The AIT will move into its new complex later this year.
The site spreads over 6.5 hectares, including Chinese gardens, in Taipei's Neihu district. However U.S. lawmakers have continued to lobby to support Taiwan, and Washington still sells hundreds of millions of dollars of weapons to Taiwan, despite China's objections.
According to Jonathan Sullivan, director of the China Policy Institute at University of Nottingham, it's possible that the Trump administration has prevented its highest figures from attending the ceremony in order to ensure Beijing cooperates with the US's attempts to denuclearize North Korea.
Earlier in the day, Beijing reacted sharply to the inauguration and said the presence of United States representatives at the inauguration may pose as an interference in China's internal affairs.
China's hostility towards Taiwan has grown since President Tsai was elected in 2016.
In the face of this rift, the United States still maintains ties with Taiwan through "unofficial" channels like AIT. Tsai, who leads the ruling Democratic Progressive Party, has refused Beijing's demand that she recognize Taiwan as a part of China, leading to a prolonged freeze in relations that had been gradually warming under her predecessor, Ma Ying-jeou of the pro-unification Nationalist Party.
A USA bill titled "Taiwan Travel Act" was passed unanimously by Congress and signed into law by Trump in March, which stipulates that the US administration should conduct more high-level official exchanges with Taiwan.