Critics argue the FTO designation could exacerbate an already dire situation where millions of civilians rely on aid.

The U.S. State Department on Tuesday said it was implementing the designation of Yemen's Iran-aligned Houthi movement as a "foreign terrorist organization" after President Donald Trump's call for the move earlier this year.

Hundreds of attacks on commercial shipping in the Red Sea and the Gulf of Aden earned Yemen-based Ansarallah, commonly called "Houthis," a designation as a foreign terrorist organization.