epa04681504 US Secretary of State John Kerry (L) and Iranian Foreign Minister Mohammad Javad Zarif (R) at the start of talks on Iran’s nuclear programme, in Lausanne, Switzerland, 27 March 2015. The chief diplomats of the United States and Iran launched a final stretch of talks to hammer out key elements of a wide-ranging nuclear deal that could mend Tehran’s relations with the West. EPA/BRENDAN SMIALOWSKI / POOL