U.S. Secretary of State Marco Rubio said Tuesday that the State Department has begun formal proceedings to label the Muslim Brotherhood a terrorist organization, a step that would bar the movement from operating in the United States once the review is complete. Speaking at a press conference, Rubio described the Islamist group as “deeply concerning” and noted that officials are collecting evidence on several of its regional branches to buttress the designation and withstand anticipated legal challenges. Rubio added that the department is also examining related organizations, including the Council on American-Islamic Relations, although no final decision has been made. The move advances a long-standing pledge by the Trump administration and security-policy advocates who have pushed for the listing for years.