Iran's President Hassan Rouhani waves as his motorcade leaves Tehran's Mehrabad Airport upon his arrival from New York Saturday, one day after he spoke to President Obama by phone. Atta Kenare /AFP/Getty Images hide caption

itoggle caption Atta Kenare /AFP/Getty Images

Iranian President Hassan Rouhani at the U.N. on Tuesday. Ray Stubblebine /Reuters/Landov hide caption

itoggle caption Ray Stubblebine /Reuters/Landov

President Obama addresses the 68th session of the United Nations General Assembly at the United Nations in New York. Timothy Clary/AFP/Getty Images hide caption

itoggle caption Timothy Clary/AFP/Getty Images

Iranian President Hassan Rouhani during an interview with NBC — part of a charm offensive ahead of his visit to the U.N. General Assembly. Rouzbeh Jadidoleslam/AP hide caption

itoggle caption Rouzbeh Jadidoleslam/AP

Iranian President Hassan Rouhani talks to NBC — part of a charm offensive ahead of his visit to the U.N. General Assembly in New York next week. Rouzbeh Jadidoleslam/AP hide caption

itoggle caption Rouzbeh Jadidoleslam/AP