Updated at 9:41 p.m. ET
Secretary of State Mike Pompeo on Monday blasted the head of the World Health Organization for bowing to Chinese pressure and not inviting Taiwan to attend the body's annual meeting, damaging its credibility at a crucial time.
The World Health Assembly started on Monday amid the worst pandemic in modern history.
Taiwan has won worldwide plaudits for its deft handling of the coronavirus, despite close links to China, where the disease first emerged. The self-ruled island has reported just 440 confirmed cases and seven virus-related deaths.
But since it is not a United Nations member, Taiwan required an invitation to attend the assembly as an observer — which was not forthcoming, despite a strong push in recent weeks with backing from the United States, Japan, New Zealand and others.
The Chinese government in Beijing considers Taiwan a province of China and says the central government represents the island's interests sufficiently in the WHO.
Pompeo said WHO Director-General Tedros Adhanom Ghebreyesus had the legal power and precedent to include it this year.
"Yet, he instead chose not to invite Taiwan under pressure from the People's Republic of China (PRC). The Director-General's lack of independence deprives the Assembly of Taiwan's renowned scientific expertise on pandemic disease, and further damages the WHO's credibility and effectiveness at a time when the world needs it the most," Pompeo said in a statement.
Taiwan attended the health assembly as an observer from 2009 to 2016, when relations with China were warmer.
In a statement on Monday, Taiwan's Foreign Minister Joseph Wu expressed "deep regret and strong dissatisfaction that the World Health Organization Secretariat has yielded to pressure from the Chinese government."
Taiwan had decided to drop the issue for now, but Wu said it would follow up later in the year on a proposal submitted to the WHO by its diplomatic allies to review the island democracy's status in light of its handling of COVID-19.
Meanwhile, Wu said Taiwan will continue to provide "big-hearted" assistance to others, donating millions of masks and other medical equipment.
A handful of WHA delegates advocated Taiwan's participation in remarks during the proceedings on Monday.
China's Permanent Representative to the UN office in Geneva, Chen Xu, said such comments "seriously violated" relevant UN resolutions and "undermined the global solidarity against the pandemic."
"China strongly protests and firmly opposes this behavior," he said through a translator. "The Taiwan authorities refused to accept the 'one China' principle. As a result, the political basis for its participation in the WHA no longer exists."