President Mahmoud Ahmadinejad is accused of economic failures
Iranian President Mahmoud Ahmadinejad has registered to fight for a second term in office in June's presidential vote, Iranian media report.
He went to the interior ministry and officially registered his candidacy in the 12 June poll, reports said.
The five-day registration period for candidates opened on 5 May.
Mr Ahmadinejad faces challenges from several quarters, including a former head of Iran's Revolutionary Guards and leading reformist Mir-Hossein Mousavi.
Mr Ahmadinejad still has the backing of key parts of the state machine, military and media, but has been accused of failing to tackle poverty, high prices and unemployment.
Candidates are invited to register to run in the vote and are then screened by the conservative electoral watchdog body, the Council of Guardians.
Earlier, the former Revolutionary Guards chief, Mohsen Rezai, registered his candidacy.
Reformist Mir-Hossein Mousavi may be Mr Ahmadinejad's toughest rival
He is seen as a conservative, but has been highly critical of Mr Ahmadinejad.
Mr Rezai is one of five leading Iranians wanted by Argentina for their alleged role in a 1994 bombing.
The attack at a Jewish organisation killed 85 people. Iran insists that it had nothing to do with the attack.
But correspondents say Mr Rezai is not regarded as a leading challenger for the presidency - that is probably Mr Mousavi.
Neither he nor his fellow reformist hopeful Mehdi Karroubi have yet formally registered their intention to run, though observers expected them to make up a four-man race.
Analysts say they will be hoping Mr Rezai's decision to run will weaken support for Mr Ahmadinejad by splitting the conservative vote.
But they, too, must be wary of splitting their potential support, they say.