Tehran, Iran (CNN) -- Iranian President Mahmoud Ahmadinejad has replaced Foreign Minister Manouchehr Mottaki, state-run Iranian media reported Monday.
Ahmadinejad appointed Ali Akbar Salehi, current nuclear chief and secretary of the Supreme National Security Council, as the interim head of the Foreign Ministry, according to the semi-official Fars news agency.
In a letter, the president thanked Mottaki for his service, according to Fars and the official Islamic Republic News Agency.
Neither report said why the move was made.
Mottaki has been one of the public faces in the international debate over Iran's nuclear program and is currently on an official visit to Senegal, according to state media.
"This move is pure Ahmadinejad: abrupt, and made even while his Foreign Minister was very far afield in Africa," said Scott Peterson, author of recently-published "Let the Swords Encircle Me: Iran - A Journey Behind the Headlines." "Rumors of Mottaki's imminent dismissal have swirled for more than two years, and conservatives have increased calls for him to be removed since the UN imposed a fourth round of sanctions on Iran last June."
Peterson said that removing Mottaki also helps President Mahmoud Ahmadinejad stengthen his influence on external affairs where the former Foreign Minister had been seen as challenging to him.
Salehi had worked as the country's representative to the International Atomic Energy Agency, which has been attempting to monitor the nation's nuclear program.
Tehran maintains that the program exists for peaceful purposes, but the United States and other Western nations have expressed concern that the program's goal is the production of nuclear weapons.
He served as interim head of the Foreign Ministry from 2007 to 2009, while working as under-secretary general of the Organization of the Islamic Conference, according to the IRNA.
Educated at the American University of Beirut, Salehi later received a doctorate in technical sciences in the United States in 1977, it said.
He served as an associate professor and chancellor of Sharif University of Technology as well as head of the Atomic Energy Organization of Iran, the IRNA reported.
His likely successor as nuclear chief is Mohammad Ghanadi Maraghei, current head of the Nuclear Science and Technology Research Institute, it said.
CNN's Reza Sayah and Shirzad Bozorgmehr contributed to this report.