The accord was announced on Tuesday by Iranian Foreign Minister Mohammad Javad Zarif and the European Union's policy chief Federica Mogherini in a joint statement in the Austrian capital.
Iranian Foreign Minister Mohammad Javad Zarif called the deal a "win-win" solution to end "an unnecessary crisis and open new horizons for dealing with serious problems that affect our international community."
"I believe this is a historic moment. We are reaching an agreement that is not perfect for everybody but it is what we could accomplish and it is an important achievement for all of us," said Zarif.
"Today could have been the end of hope on this issue, but now we are starting a new chapter of hope."
Mogherini said the decision demonstrated that "diplomacy, coordination, cooperation can overcome decades of tensions and confrontations".
"It is a decision that openned a way to a new chapter in international relations," she said.
Al Jazeera's James Bays, reporting from Vienna, said that the presidents of the United States and Iran were expected to speak about the deal.
"For them it is a historic deal that would serve some kind of a re-set after decades of mistrust," he said.
- AlJazeera
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