Retired four-star Marine Corps general John R. Allen has resigned as president of the Brookings Institution, one of the world’s best-known think tanks, following an administrative reshuffle amid a federal investigation into a suspected government lobby. Qatar years ago, the company announced to employees on Sunday. The investigation focuses on whether Allen, a military commander who once led the US combat force in Afghanistan, secretly urged the Trump administration to reduce its criticism of Qatar in 2017, when Persian Gulf neighbors imposed economic sanctions on the country, accusing it of for supporting Islamic extremism, according to court records. Allen was released, Brookings said last week. Allen did not immediately respond to a request for comment Sunday afternoon. The margins of the Brookings think tanks were demobilized amid a federal investigation In an email to officials Sunday afternoon, Glenn Hutchins and Susan Nora Johnson, co-chairs of the Brookings Institution, said Ted Gayer, a senior financial associate, had taken over as chairman. The note thanked Allen for his “leadership in successfully guiding the institution during the pandemic” and did not explicitly mention the federal investigation. “Brookings seeks to maintain high ethical standards in all its activities,” Hutchins and Nora Johnson wrote in an email to the Washington Post. “Our policies on the independence and integrity of research reflect these values.” This is a growing story that will keep you updated.