World powers and Iran have formally announced a comprehensive nuclear accord.
Federica Mogherini, the European Union's foreign policy chief, said: "Today is an historic day."
She added that it was a great honour "for us to announce that we have reached an agreement on the Iranian nuclear issue".
Supreme Leader Ayatollah Ali Khamenei said has said that Iranian opposition to the "arrogant" United States will not change despite a nuclear deal with world powers,
He added that Tehran remains sharply at odds with US policy in the Middle East.
Khamenei made the comments in an address marking the end of the Muslim holy month of Ramadan.
He said politicians should examine the agreement to ensure national interests were preserved, as Iran would not allow the disruption of its revolutionary principles or defensive abilities. American leaders sought Iran's "surrender", he said. Iran would not welcome war but if there were one, the United States would be humiliated.
Prime minister Netanyahu has likened the nuclear deal with Iran to the unsuccessful 1994 deal on North Korea's nuclear programme.
An end to Iranian nuclear question could soon be a reality after years of hard and often tense negotiations.