The State Department has officially designated the group Ansarallah, also known by various other names such as Ansar Allah and Supporters of God, as a foreign terrorist organization. This decision was made after consulting with the Attorney General and the Secretary of the Treasury and is based on a review of relevant evidence as outlined in section 219 of the Immigration and Nationality Act. The announcement, signed by the then Secretary of State Michael R. Pompeo, is recorded in the Federal Register, formally stating the group's designation.
Simple Explanation
The State Department decided that a group called Ansarallah, which has other names like Ansar Allah, is dangerous and is now officially labeled as a terrorist group. They did this after getting advice from other important people in the government and checking lots of information.