The United States has formally completed its withdrawal from the World Health Organization, the Trump administration announced Thursday, one year after President Donald Trump signed an executive order initiating the process.

The decision was confirmed in a joint announcement by the Department of Health and Human Services and the Department of State.

A senior HHS official said the administration concluded that the WHO had “strayed from its core mission” and had acted “contrary to U.S. interests in protecting the American public on multiple occasions.”

Federal officials cited the organization’s handling of the COVID-19 pandemic as a central concern, arguing that the WHO delayed declaring the outbreak a global health emergency and unfairly criticized the Trump administration for early measures such as restricting travel from certain countries.

The administration also contended that the United States contributed disproportionately to the organization’s budget compared with other nations, including China, and noted that no American has ever served as the WHO’s director-general.

Public health experts sharply criticized the withdrawal, warning that it could weaken the United States’ ability to detect and respond to health threats both domestically and overseas.

“The U.S. withdrawal from the World Health Organization is a shortsighted and misguided abandonment of our global health commitments,” said Dr. Ronald Nahass, president of the Infectious Diseases Society of America. “Global cooperation and communication are critical to keeping our citizens safe because germs do not respect borders.”

Nahass said the move would hamper U.S. monitoring of emerging diseases such as Ebola, complicate efforts to track and respond to seasonal influenza outbreaks, and reduce the country’s ability to match vaccines to circulating flu strains.

“Withdrawing from the World Health Organization is scientifically reckless,” he added. “Global cooperation is not a luxury. It is a biological necessity.”