When Joe Biden took office as president in 2021, he removed this classification for the Houthi movement, which Trump had issued at the end of his previous term.
Biden's decision came after aid organizations warned that they would have to withdraw from Yemen due to the terrorist classification, since they are forced to work with the movement, which controls large parts of the country, including the capital Sanaa.
When the war in Gaza broke out on October 7, 2023, the Iran-backed group began attacking ships in the Red Sea, which led the White House to re-list them on its terror list. However, with a milder classification, which allowed aid organizations to continue their work in the war-torn country.
But now Trump has thus tightened the classification, which can take weeks before it comes into effect.