Iranian Supreme Leader, Ayatollah Khamenei, on Thursday confirmed Hassan Rowhani as President.
Mr. Khamenei also handed Mr. Rowhani the letter of appointment.
Mr. Rowhani is to be sworn in on Saturday in front of parliament.
Analysts however said difficult times lie ahead for the re-elected reformist, who first and foremost will need to save the 2015 nuclear deal made with six world powers from being scuppered by U.S. President Donald Trump and hardliners in Tehran.
Trump has expressed scepticism about the nuclear agreement, which significantly reduced the scope of Iran’s nuclear programme in exchange for lifting sanctions, and has sought other ways to keep the pressure on Tehran.
NAN reports that Rouhani won re-election in a landslide on May 30.
Of the 41 million votes cast, the Interior Ministry said, Rouhani won 23 million (or 57 per cent), soundly defeating his chief opponent, Ebrahim Raisi, who received 15.7 million (38.5 per cent).
The ministry said turnout was heavy, with more than 70 per cent of Iran’s 56 million voters casting ballots.