Bill Gates participates in a discussion at the Economic Club of Washington on June 24, 2019 in Washington. Alex Wong/Getty Images

Microsoft founder Bill Gates has denounced US President Donald Trump's decision to halt funding to the World Health Organization in an early morning tweet.

"Halting funding for the World Health Organization during a world health crisis is as dangerous as it sounds," Gates said in a tweet on his official account.

“Their work is slowing the spread of COVID-19 and if that work is stopped no other organization can replace them,” he said, adding the world needs the WHO “now more than ever.”

Trump announced Tuesday he is halting funding to the WHO while a review is conducted into its handling of the coronavirus pandemic.