Economic sanctions imposed by the US and the EU on Iran have now been lifted. Photo: AFP/Getty Images on BBC News
Iran "has opened a new chapter" in its ties with the world, President Hassan Rouhani said, hours after economic sanctions on Tehran were lifted.
On Saturday the international nuclear watchdog, the IAEA, confirmed Iran had complied with a deal designed to prevent it developing nuclear weapons.
Mr Rouhani, quoted by Press TV, said the deal did not harm any nation. Most Western governments hailed the move but Israel's PM insists Tehran still wants to build a nuclear bomb.
"Without an appropriate reaction to every violation, Iran will realise it can continue to develop nuclear weapons, destabilise the region and spread terror," Benjamin Netanyahu said. Before the deal, the BBC's Bethany Bell reports from Vienna, Iran could have enriched enough uranium, had it so wanted, to make a nuclear bomb within a matter of weeks.
Now it would take more than a year and it is something international inspectors would see, she says.
Mr Rouhani said everyone was happy with the deal, apart from those he described as warmongers in the region - Israel and hardliners in the US Congress.
"We Iranians have reached out to the world in a sign of friendliness, and leaving behind the enmities, suspicions and plots, have opened a new chapter in the relations of Iran with the world," he said in a statement to the nation on Sunday morning.
The lifting of sanctions was "a turning point" for Iran's economy, he added, saying the country needed to be less reliant on oil revenues.
EU foreign policy chief Federica Mogherini said Iran's compliance and the lifting of sanctions would contribute to improved regional and international peace and security.
Yukiya Amano, the head of the IAEA, will visit Tehran on Sunday for talks on how to continue monitoring Iran's nuclear programme.
"A lot of work has gone into getting us here, and implementation of this agreement will require a similar effort," he said.
As part of the deal, Iran had to drastically reduce its number of centrifuges and dismantle a heavy-water reactor near the town of Arak, both of which could be used in creating nuclear weapons. The reactor was then filled with concrete.
Estimates say close to $100bn (£70bn) of Iranian assets will be unlocked under the deal. Hours before the sanctions were lifted, Iran's transport minister was quoted by the official Irna news agency on Saturday as saying a deal had been struck with the Airbus consortium in Europe to buy 114 new passenger planes.
And in November, Iran said it expected to immediately double its daily export of 1.1m barrels of crude oil as soon as the sanctions were lifted.
Iran has always maintained its nuclear programme is peaceful, but opponents of the deal - such as some US Republicans - say it does not do enough to ensure the country cannot develop a nuclear bomb.
On Saturday, the IAEA, said its inspectors had verified that Tehran had taken the required steps. As a result, US Secretary of State John Kerry ordered that US nuclear-related economic sanctions against Iran be lifted.
Speaking in Vienna, where he had been holding talks with his Iranian counterpart, Mr Kerry said Iran had "undertaken significant steps" which many people "doubted would ever come to pass".
The IAEA said it had installed a device at the Natanz plant to monitor Iran's uranium enrichment activities in real time, in order to verify that uranium enrichment levels were kept at up to 3.67% as agreed in the deal with world powers.
Earlier on Saturday it emerged that Iran had released Washington Post reporter Jason Rezaian and three other Iranian-American prisoners in an apparent prisoner swap with the United States.
Rezaian, 39, was jailed on charges, including espionage, last November. The US said it was offering clemency to seven Iranians being held in the US for sanctions violation.
Mr Kerry said said he was "very happy to say that as we speak five Americans have been released from custody and they should be on their way home to their families shortly".
A fifth American, Matthew Trevithick, was also released on Saturday. President Barack Obama would give more details of the releases later, Mr Kerry said.
In July 2015, Iran agreed a landmark nuclear deal with six world powers to limit its sensitive nuclear activities for more than a decade in return for the lifting of crippling sanctions. The US is confident the agreement will prevent Iran from obtaining a nuclear weapon. Iran says it has the right to nuclear energy - and stresses that its nuclear programme is for peaceful purposes only.
The sanctions have cost Iran more than more than $160bn (£102bn) in oil revenue since 2012 alone. Once they are lifted, the country will be able to resume selling oil on international markets and using the global financial system for trade. Iran has the fourth largest oil reserves in the world and the energy industry is braced for lower prices. Iran will also be able to access more than $100bn in assets frozen overseas.