Iran and six major world powers have reached a nuclear deal, capping over a decade of negotiations with an agreement that could transform the Middle East.
US president Barack Obama hailed a step towards a "more hopeful world", while Iran's president Hassan Rouhani, said it proved that "constructive engagement works".
But Israel said it would do what it could to kill a deal that it called an "historic surrender".
Under the deal, sanctions imposed by the US, EU and UN will be lifted in return for Iran agreeing long-term curbs on a nuclear programme that the West has suspected was aimed at creating a nuclear bomb.
The agreement is a momentous political victory for both Obama, who has long promised to reach out to historic enemies, and Rouhani, a pragmatist elected two years ago on a vow to reduce the isolation of his nation of 80 million people.
Israeli PM Benjamin Netanyahu called the deal "a bad mistake of historic proportions". His deputy foreign minister, Tzipi Hotovely, called the deal an "historic surrender".