President Donald Trump is pulling the U.S. out of the World Health Organization, raising concerns about the U.N. agency's ability to fight diseases and respond to emergencies around the globe without its biggest funder.

The exit will cut a huge chunk from the World Health Organization’s budget, but the short-term financial gain for the US could come at the cost of disease outbreaks flaring up across the world.

Ooh, that’s a big one,” Donald Trump said Monday as he signed an executive order – one of dozens during his first hours as president – to withdraw the United States from the World Health Organization.