Iran's Supreme Leader Ayatollah Ali Khamenei delivers a sermon during morning prayers for the Eid al-Fitr holiday, marking the end of the holy month of Ramadan. He signaled his approval of the nuclear agreement with Western powers but reiterated that Tehran's policy toward the "arrogant" United States would not change. Reuters/Landov hide caption

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An International Atomic Energy Agency inspector cuts a uranium enrichment connection at Iran's Natanz facility, 200 miles south of Tehran, in 2014. This week's nuclear deal gives the IAEA up to 150 inspectors to monitor Iran for compliance. Kazem Ghane/AP hide caption

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A man walks past a poster advertising travel to Tehran, Iran, in Los Angeles on July 14. A nuclear deal between Iran and six world powers lifts some sanctions against Iran, but most U.S. sanctions will remain in place. Lucy Nicholson/Reuters/Landov hide caption

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Shoppers make their way in a Tehran bazaar. Once international sanctions are lifted, $100 billion from Iranian oil sales will be released from escrow accounts. Vahid Salemi/AP hide caption

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An Iranian family walks past anti-U.S. graffiti on the wall of the former U.S. embassy in Tehran on Tuesday. President Hassan Rouhani told Iranians that "all our objectives" have been met by a nuclear deal agreed upon Tuesday after talks with six world powers, including the U.S. Atta Kenare/AFP/Getty Images hide caption

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Iranian Foreign Minister Javad Zarif (center) with U.S. Secretary of State John Kerry in Lausanne, Switzerland, after talks over Iran's nuclear program wrapped up in April. Brendan Smialowski/AP hide caption

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Iranian Supreme Leader Ayatollah Ali Khamenei, seen here in a photo released by his official website Thursday, stopped short of giving his endorsement to the framework nuclear deal struck last week. AP hide caption

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Iran's President Hassan Rouhani, speaking in Tehran in February, has spoken out in favor of nuclear negotiations and opening Iran to the world. But he has faced criticism from hard-liners at home. Ahmad Halabisaz/Xinhua/Landov hide caption

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Secretary of State John Kerry (left), and Russian Foreign Minister Sergey Lavrov (right) wait for the start of a meeting at the Beau Rivage Palace Hotelin Lausanne, Switzerland, on Sunday to discuss a nuclear deal on Iran. Brendan Smialowski/AP hide caption

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Secretary of State John Kerry delivers a statement about the recently concluded round of negotiations with Iran over their nuclear program at the International Olympic Museum in Lausanne, Switzerland, on Saturday. Brian Snyder/Reuters/Landov hide caption

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Tom Cotton, R-Ark., the freshman senator and Harvard graduate senator with a record of tough talk on foreign policy. Carolyn Kaster/AP hide caption

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A letter from U.S. senators suggests the lawmakers "not only do not understand international law, but are not fully cognizant of the nuances of their own Constitution," says Iranian Foreign Minister Mohammad Javad Zarif. Kyodo /Landov hide caption

itoggle caption Kyodo /Landov

Israeli Prime Minister Benjamin Netanyahu speaks before a joint meeting of Congress on Capitol Hill in Washington on Tuesday. Netanyahu said the world must unite to "stop Iran's march of conquest, subjugation and terror." House Speaker John Boehner of Ohio (left) and Sen. Orrin Hatch, R-Utah, listen. Andrew Harnik/AP hide caption

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U.S. Secretary of State John Kerry (right) and Iran's Foreign Minister Javad Zarif (left) shake hands as Oman's Minister for Foreign Affairs Yussef bin Alawi (second from right) and the former EU top diplomat Catherine Ashton watch in Muscat, Oman on Nov. 9. Iran is holding talks with six world powers in Vienna this weekend in advance Monday's deadline for a deal on Iran's nuclear program. Nicholas Kamm/AFP/Getty Images hide caption

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