International Atomic Energy Agency chief Mohamed ElBaradei has been formally re-appointed to the post for another four-year term.
Mr. ElBaradei, who has been the Director General of the U.N. agency since 1997, was unanimously approved and immediately sworn-in Monday at an IAEA general conference in Vienna.
The agency's board of governors had re-nominated him for the post in June after the United States dropped its opposition to a third term for Mr. ElBaradei.
The United States viewed the former Egyptian diplomat as being too soft on Iran's nuclear activities that Washington says are a cover for an atomic weapons program. Iran denies the charge.
Last week, the IAEA board adopted a resolution saying Iran could be referred to the U.N. Security Council for possible sanctions if Tehran fails to meet international concerns about its nuclear program.