President Donald Trump has notified the United Nations and the US Congress that he plans to withdraw the country from the World Health Organization (WHO).
In April, Mr Trump accused the UN body, which coordinates global public health efforts, of failing “in its basic duty” during the coronavirus pandemic.
President Trump claimed the WHO had mismanaged the initial outbreak, and of covering up the spread of the virus.
Stéphane Dujarric, spokesman for the UN secretary-general, confirmed the US had notified it of its withdrawal, effective as of 6 July 2021.
Mr Trump has faced intense criticism of his own handling of the coronavirus outbreak in the United States, where more than 3 million people have tested positive for the disease.
133,000 Americans have died from Covid-19 - a quarter of the global total.
American news network, CBS News, has reported that the President’s latest move comes after the WHO refused to engage with requested reforms demanded by Washington.
"Because they have failed to make the requested and greatly needed reforms, we will be today terminating our relationship," the official was quoted as saying.
The United States is the WHO’s largest individual funder. In 2019 it gave $400 million (£316 million) - around 15% of its overall budget.
It may take more than a year for the US to officially withdraw from the WHO, owing to a 1948 Congressional resolution that forces the government to give a year’s notice before leaving.
In a White House press conference in April, Mr Trump said “I am directing my administration to halt funding while a review is conducted to assess the World Health Organization's role in severely mismanaging and covering up the spread of the coronavirus.”
"The WHO failed in its basic duty and it must be held accountable," he added.
Then in late May he told reporters: "We will be terminating our relationship with the World Health Organization and directing those funds" to other global public health charities.
He also claimed that China had “instigated a global pandemic”, and said the Asian superpower had “total control” over the WHO.
Mr Trump has not provided evidence for his claims.
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