Iran appears to have built an extension to part of its Parchin military site since May, the U.N. nuclear watchdog said in a report on Thursday delving into a major part of its inquiry into possible military dimensions to Tehran's past atomic activity. A resolution of the International Atomic Energy Agency's Parchin file, which includes a demand for fresh IAEA access to the site, is a symbolically important issue that could help make or break Tehran's July 14 nuclear deal with six world powers.