Hassan Rouhani is the New President of Iran

Reformist-backed cleric Hassan Rouhani has won Iran's presidential election, securing just over 50% of the vote and so avoiding the need for a run-off.

Crowds gathered in Tehran to hail Mr Rouhani, who said he had achieved a "victory of moderation over extremism".

A turnout of 72.2% was registered of the 50 million Iranians who were eligible to vote for the successor to Mahmoud Ahmadinejad.

Tehran Mayor Mohammad Baqer Qalibaf was well behind in second place.

Supreme Leader Ayatollah Ali Khamenei congratulated Mr Rouhani on his victory.

"I urge everyone to help the president-elect and his colleagues in the government, as he is the president of the whole nation," he said.

Ayatollah Khamenei will ratify the vote on 3 August and the new president will then take the oath in parliament.

Mr Rouhani, who has pledged greater engagement with Western powers, said: "This victory is a victory for wisdom, moderation and maturity... over extremism."

But he also urged the world to "acknowledge the rights" of Iran.