U.S. Secretary of State John Kerry said on March 15 that most of the differences still preventing a nuclear deal with Iran are political rather than technical.
Kerry told the U.S. television station CBS that "by and large, most of the differences now are political decisions that need to be made in order to fulfill the promise of proving to the world that a program is peaceful."
Kerry said that Tehran "to its credit has thus far lived up to every part of the agreement we made over a year ago."
Kerry is meeting with Iranian Foreign Minister Mohammed Javad Zarif on March 15 in Lausanne, to try and resolve remaining differences between Tehran and six world powers on a political deal before an end-of-March deadline.
Negotiators would then push forward to try to reach a permanent agreement by the end of June.