He said he is doing this because the WHO has failed to deal with the coronavirus pandemic and it has become biased towards China.
Earlier this month President Trump froze all U.S. funding to the WHO.
The U.S. gives the WHO approximately $450 million a year. China meanwhile pays approximately $50 million a year — although Beijing had recently announced a $2 billion injection of funds.
Trump has accused China of not passing on truthful information about COVID-19.