President Donald Trump on Monday gave the World Health Organization (WHO) 30 days to "commit to major substantive improvements" or the US will permanently freeze funding for the body and reconsider its membership.
Trump issued the stark warning in a letter he posted on Twitter, accusing the organization of ignoring reports of the novel coronavirus spreading in China in December and failing to share "critical information" regarding the outbreak.
In April, Trump said the WHO was China-centric and temporarily cut funding with a review pending.
In the strongly-worded letter, the president said the organization made "grossly incorrect" or "misleading" claims regarding the virus, which has infected more than 4.8 million people worldwide.
Trump recalled his decision to ban travel from China in January, which he said WHO Director-General Tedros Adhanom Ghebreyesus opposed, but praised China's "strict domestic travel restrictions."
The WHO's decision to declare the coronavirus a pandemic was also among the criticisms the US president leveled against the international health body. He said when the WHO announced it was a pandemic, the virus had already killed more than 4,000 people and infected 100,000 others in 114 countries.
"Throughout this crisis, the World Health Organization has been curiously insistent on praising China for its alleged 'transparency'," Trump wrote in the letter, in which he also accused Beijing of depriving the world of critical information on the outbreak.
He told the WHO chief that his organization's responses to the pandemic "have been extremely costly for the world," demanding the body to "demonstrate independence from China."
Stating that his administration is in talks with WHO officials, Trump said urgent action is needed and "we don't have time to waste."
"I cannot allow American taxpayer dollars to continue to finance an organization that, in its present state, is so clearly not serving America's interests," he concluded.
The virus has killed more than 90,000 people in the US, while more than 318,000 are dead worldwide since December when the virus was first detected in Wuhan city, China.
