Secretary of State John Kerry (right) and Iranian Foreign Minister Javad Zarif shake hands as Omani Minister Responsible for Foreign Affairs Yussef bin Alawi and former EU top diplomat Catherine Ashton watch Nov. 9 in Muscat, Oman. Nicholas Kamm /AFP/Getty Images hide caption

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A worker rides a bicycle in front of the Bushehr nuclear power plant in Iran in 2010. Iran and six world powers are meeting in Vienna this week with the goal of reaching a comprehensive deal on Iran's nuclear program before a July 20 deadline. Majid Asgaripour/Mehr News Agency/AP hide caption

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Iranian Foreign Minister Mohammad Javad Zarif (right) speaks during a joint press conference with his Swedish counterpart Carl Bildt in Tehran on Tuesday. Bildt is visiting to try to bolster the temporary nuclear deal on Iran's nuclear program. Behrouz Mehri/AFP/Getty Images hide caption

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UN experts are inspecting the heavy water production plant in Arak, Iran, on Sunday. The visit is the first test of an interim deal Iran struck with the West in November. Hamid Foroutan/AFP/Getty Images hide caption

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Inspectors from the International Atomic Energy Agency are scheduled to visit Iran's heavy-water reactor in the city of Arak on Sunday as part of an international deal on the country's nuclear program. Hamid Forutan/EPA/Landov hide caption

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Iranian Foreign Minister Mohammad Javad Zarif speaks during a news conference earlier this month. Ahmad Al-Rubaye/AFP/Getty Images hide caption

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April 2010: Iranian President Mahmoud Ahmadinejad unveils a sample of the third generation centrifuge for uranium enrichment during a ceremony in Tehran on April 9, 2010. Iran says its nuclear ambitions are peaceful. Behrouz Mehri/AFP/Getty Images hide caption

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