The withdrawal takes effect one year after President Donald Trump signed an executive order initiating the process.
As a result, the United States is no longer a member of the UN’s specialised health agency.
The decision revives long-running tensions between Washington and the WHO, which intensified during the Covid-19 pandemic.
Trump previously sought to pull the U.S. out of the organisation in 2020, citing what he described as mismanagement and political bias.
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That move was later reversed under President Joe Biden.
Why the U.S. says it left
According to ABC News, the Trump administration argues that the WHO has moved away from its original mandate and has repeatedly acted against American interests.
A senior official at the Department of Health told the network that the organisation’s handling of Covid-19 remains a central grievance, particularly the timing of when the outbreak was declared a global health emergency.
Financial disputes have also played a role. The United States has been one of the WHO’s largest contributors and argues that it has paid a disproportionate share compared with other major member states.
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The United Nations, however, says the U.S. owes more than 270 million dollars in unpaid membership dues for 2024 and 2025.
The U.S. government rejects that claim, saying it is not legally obligated to pay, ABC News reports.
Experts warn of consequences
The decision has drawn criticism from infectious disease specialists.
Ronald Nahass, president of the Infectious Diseases Society of America, told ABC News that the withdrawal is “short-sighted and misguided".
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Experts warn that leaving the WHO could limit U.S. access to global disease surveillance systems used to detect outbreaks such as Ebola and to guide the selection of influenza strains for seasonal vaccines.
The WHO has said the U.S. exit will be discussed at its executive board meeting in February.
Sources: ABC News.
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