Iranian Foreign Minister Mohammad Javad Zarif, who is also Iran\'s top nuclear negotiator, waves to his well wishers upon arrival at the Mehrabad airport in Tehran, Iran, from Lausanne, Switzerland, Friday, April 3, 2015. (AP Photo/Ebrahim Noroozi) (credit:ASSOCIATED PRESS)
(02 of07)
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Iranian Foreign Minister Mohammad Javad Zarif, who is also Iran\'s top nuclear negotiator, waves to his well wishers upon arrival at the Mehrabad airport in Tehran, Iran, from Lausanne, Switzerland, Friday, April 3, 2015. (AP Photo/Ebrahim Noroozi) (credit:ASSOCIATED PRESS)
(03 of07)
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Iranians flash the victory sign as they hold their country\'s flag while waiting for arrival of Foreign Minister Mohammad Javad Zarif from Lausanne, Switzerland, at the Mehrabad airport in Tehran, Iran, Friday, April 3, 2015. (AP Photo/Ebrahim Noroozi) (credit:ASSOCIATED PRESS)
(04 of07)
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Iranian Foreign Minister Mohammad Javad Zarif, who is also Iran\'s top nuclear negotiator, waves to his well wishers upon arrival at the Mehrabad airport in Tehran, Iran, from Lausanne, Switzerland, Friday, April 3, 2015. (AP Photo/Ebrahim Noroozi) (credit:ASSOCIATED PRESS)
(05 of07)
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Iranian Foreign Minister Mohammad Javad Zarif, who is also Iran\'s top nuclear negotiator, waves to his well wishers upon arrival at the Mehrabad airport in Tehran, Iran, from Lausanne, Switzerland, Friday, April 3, 2015. (AP Photo/Ebrahim Noroozi) (credit:ASSOCIATED PRESS)
(06 of07)
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Iranians celebrate on a street in northern Tehran, Iran, Thursday, April 2, 2015, after Iran\'s nuclear agreement with world powers in Lausanne, Switzerland. (AP Photo/Ebrahim Noroozi) (credit:ASSOCIATED PRESS)
(07 of07)
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Iranians flash the victory sign while waiting for arrival of Foreign Minister Mohammad Javad Zarif from Lausanne, Switzerland, at the Mehrabad airport in Tehran, Iran, Friday, April 3, 2015.(AP Photo/Ebrahim Noroozi) (credit:ASSOCIATED PRESS)