'Sense of duty' puts veteran U.S. envoy in middle of Ethiopia conflict

Former U.N. aid chief Mark Lowcock, who worked alongside Feltman for a year, praised him as deeply knowledgeable and "unusually creative in solving problems."

"He was always good at spotting when leaders realized the direction they were heading in was going to land them in deep doo-doo and helping them change course without unhelpfully rubbing their faces in it," Lowcock, who is now a fellow at the Center for Global Development, told Reuters.