1052 GMT November 28, 2020
"In recent weeks, Mr. Rouhani has reached a conclusion to take part in the presidential elections," Hosseinali Amiri told reporters, according to IRNA.
Rouhani, a 68-year-old moderate, has been widely expected to run for a second term but has yet to formally announce his candidature for the May 19 election.
He remains popular for stabilizing the economy and ending sanctions through a nuclear deal with world powers.
The conservative camp has so far failed to settle on an obvious challenger to Rouhani, who sits atop a relatively unified coalition of moderates and reformists.
Candidates must formally announce their intention to run between April 11 and 15.
The Guardians Council will then have 10 days to approve the candidates, and has been known to block even high-profile figures such as former president Akbar Hashemi Rafsanjani, who was barred from running in 2013 and eventually threw his weight behind Rouhani.
The official campaign season is just two weeks long, and due to last from April 28 to May 17.