President Donald Trump announced Monday he is withdrawing the US from the World Health Organization, a significant move on his first day back in the White House cutting ties with the United Nations’ public health agency and drawing criticism from public health experts.

Public health experts say U.S. withdrawal from the W.H.O. would undermine the nation’s standing as a global health leader and make it harder to fight the next pandemic.

The United States will leave the World Health Organization, President Donald Trump said on Monday, saying the global health agency had mishandled the COVID-19 pandemic and other international health crises.