President Barack Obama has named Brett McGurk as the new official in charge of the U.S.-led coalition against the Islamic State group.
Retired Marine Gen. John Allen is stepping down after 13 months overseeing the effort as the president's special envoy for the global coalition to counter IS.
McGurk was Allen's deputy.
Obama is expressing his "profound gratitude" to Allen for having put off retirement from government service and taken the assignment.
Obama says he's asked McGurk to work closely with the national security team to improve relations with Iraq, and with America's partners in the region to help end the civil war in Syria, which has fueled the Islamic State group's rise.