U.S. Secretary of State John Kerry has emphasized in talks with Iranian Foreign Minister Mohammad Javad Zarif the importance of meeting the March deadline for curbing Iran's controversial nuclear program.
An unnamed U.S. official said Kerry "reiterated our desire to move toward a political framework by the end of March" during two hours of talks with Zarif on the sidelines of the Munich security conference on February 6.
Six world powers have missed two self-imposed deadlines in the last year to agree to a comprehensive deal designed to rein in Iran's nuclear program.
The group known as the P5+1 -- Britain, China, France, Germany, Russia, and the United States -- has a March 31 deadline for a political agreement and a permanent deal by June 30.
Iran would gain relief from crippling economic sanctions in exchange for cutting back on its nuclear program, which the world powers fear could be used for nuclear weapons.
Iran says its nuclear program is only for peaceful purposes.