President Donald Trump’s decision to exit the World Health Organization means the U.N. agency is losing its biggest funder.

World Health Organization chief says agency already cutting back on hiring and travel with Trump withdrawal set to hit funding.

"Unfairly onerous payments" are cited in the executive order as a reason for WHO withdrawal. Countries’ dues are a percentage of their gross domestic product, meaning that as the world’s richest nation, the United States has generally paid more than other countries.

Tania Cernuschi, a WHO staff member of 10 years who has worked on improving vaccine access, said she thought of the campaign when she could not sleep after Trump's announcement.

WHO’s constitution, drafted in New York, doesn’t have a clear exit method for member states. A joint resolution by Congress in 1948 outlined that the U.S. can withdraw with one year's notice. This is contingent, however, on ensuring that its financial obligations to WHO “shall be met in full for the organization’s current fiscal year.”

The World Health Organization said Friday it was reviewing its priorities ahead of the withdrawal of its largest donor the United States, noting the agency provides vital services to protect against health threats.

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.

The World Health Organization is drawing up a list of reasons why the U.S. should remain in the WHO for its own good, two sources familiar with the process told Reuters, as part of an attempt by its supporters to lobby incoming President Donald Trump.

The move to exit the WHO is historic and controversial. The U.S. has long been the most generous provider of humanitarian assistance.

President Donald Trump's order withdrawing the U.S. from the World Health ... headquarters in Geneva, Switzerland, it is the largest international intergovernmental health organization, and ...

GENEVA (Reuters) - Hospitals are overwhelmed in east Congo's city of Goma, treating hundreds of patients with gunshot, mortar and shrapnel wounds while many dead bodies lay in the streets, U.N. and other aid agencies said on Tuesday.

By Patrick Wingrove, Jennifer Rigby and Emma Farge NEW YORK/GENEVA (Reuters) - 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.