When international sanctions on Iran would be lifted has emerged as one of the largest remaining stumbling blocks to an agreement to constrain Tehran’s nuclear program by a March 31 deadline, according to U.S., European and Iranian officials. Tehran’s negotiators in Switzerland, according to these diplomats, have hardened their position that United Nations sanctions on their country be repealed at the front end of any deal reached this month with the U.S. and other global powers. The U.S. and its European allies are demanding the U.N.’s sanctions be suspended or terminated in a phased time-frame over years. They believe sanctions relief should only come […]