President Donald Trump signed an executive order Wednesday banning transgender athletes from participating in women's sports, fulfilling a promise that was at the center of his 2024 campaign.

Schools receiving taxpayer money are "on notice" that they could lose federal funding if they don't comply with the order, Trump said before signing the document amid a crowd of supporters at the White House.

It is the fourth order directly targeting transgender people the president has signed since he took office Jan. 20.