President Donald Trump has formally started the withdrawal of the United States from the World Health Organization, making good on threats over the UN body’s response to the coronavirus, officials said Tuesday.

The United States is the largest financial contributor to the WHO — which leads the fight on global maladies from polio to measles to mental health — but it has increasingly been in Trump’s crosshairs as the coronavirus takes a heavy toll.

After threatening to suspend the $400 million in annual US contributions and then announcing a withdrawal, Trump has formally informed UN Secretary-General Antonio Guterres that he has started the US pullout, a State Department spokesperson said.

The withdrawal is effective in one year — July 6, 2021 — and Joe Biden, Trump’s presumptive Democratic opponent, is virtually certain to stop it and stay in the WHO if he defeats Trump in the November election.

Stephane Dujarric, the spokesman for Guterres, confirmed that the United States gave its notice.

Under conditions set when the United States entered the World Health Organization in 1948, Washington has to give a one-year notice to pull out — and meet its remaining assessed financial obligations, Dujarric said.

The news was also tweeted by Sen. Robert Menendez, the top Democrat on the Senate Foreign Relations Committee.

The US President on several occasions has accused the World Health Organization of bias toward China, saying it ignored early signs of human-to-human transmission of the deadly virus. While many public health advocates share some criticism of the WHO, they question what other powers the world body had other than to work with China, where COVID-19 was first detected late last year.

Critics say Trump is seeking to deflect criticism from his own handling of the pandemic in the United States, which has suffered by far the highest death toll of any nation.