epa04690113 (L-R) US Secretary of State John Kerry Iranian Foreign Minister Mohammad Javad Zarif, and EU High Representative for Foreign Affairs and Security Policy Federica Mogherini, react during a press event after the end of a new round of Nuclear Iran Talks in the Learning Center at the Swiss federal Institute of Technology (EPFL),in Lausanne, Switzerland, 02 April 2015. The agreement on key elements of a nuclear agreement over Iran’s conroversial nuclear programme is a major step toward reaching a final deal, Iran and six world powers say. The final deal, which is to be concluded by the end of June, will limit Iran’s uranium enrichment programme and its nuclear research and development programme, they said. EPA/JEAN-CHRISTOPHE BOTT