Ambassador Stephen D. Mull has served as Lead Coordinator for Iran Nuclear Implementation since August 2015, in which capacity he has led U.S. government interagency efforts and diplomacy to implement the Joint Comprehensive Plan of Action (JCPOA) to constrain Iran’s nuclear program. Prior to this position, he was the U.S. Ambassador to the Republic of Poland from 2012 until 2015, during which assignment he supported a significant growth of U.S. exports to Poland and expanded U.S.-Polish military cooperation within NATO in response to Russian aggression against Ukraine. Previously, he served as Executive Secretary of the State Department from 2010 until 2012, in which capacity he coordinated responses to a wide range of crises and managed the Department’s support for the Secretary of State. Before then, he had served since August 2008 as Senior Advisor to Under Secretary of State for Political Affairs William Burns, in which position he coordinated U.S. diplomatic efforts on Iran, managed the State Department’s crisis response during the Russian-Georgian war of August 2008, and led negotiations on a range of issues, including the agreement permitting the flight of U.S. military resupply flights to Afghanistan through Russian airspace, saving taxpayers over $25 million.

Ambassador Mull has worked in a broad range of positions focused on U.S. national security and U.S. interests in countries undergoing volatile transitions to democracy. He was Acting Assistant Secretary of State for Political-Military Affairs from January 2007 through August 2008, focusing on diplomatic coordination with the U.S. military. He served as U.S. Ambassador to the Republic of Lithuania 2003-2006, during which period he oversaw efforts to bring Lithuania into the NATO alliance. He was Deputy Chief of Mission at the U.S. Embassy in Jakarta, Indonesia from 2000 to 2003, during a period of significant terrorist threats and political instability. He covered opposition politics in apartheid South Africa’s transition to democracy from 1986-90, winning the State Department’s top prize for political reporting. He also reported on Poland’s democratic movement during communism from 1984-86. In Washington, he has served as Deputy Executive Secretary of the Department, Director of the Office of Southern European Affairs and Deputy Director of the Operations Center, the State Department’s crisis management center.

Ambassador Mull is the recipient of the Secretary of State’s Distinguished Service Award, two Presidential Meritorious Service Awards, two Distinguished Honor Awards, the Baker-Wilkins Award for Outstanding Deputy Chief of Mission, two Superior Honor Awards, and more than a dozen Senior Foreign Service performance awards. He joined the Foreign Service in March 1982, and holds the personal rank of Career Ambassador, the highest rank in the U.S. Foreign Service. He is a 1980 graduate of Georgetown University’s School of Foreign Service.