More than 600 candidates registered to compete in the presidential race. Iranian nationals with political or clerical credentials are eligible to register, though the 12-member Guardian Council has the final say on candidates.
Deputy Interior Minister Solat Mortazavi said the final list of candidates would be announced Wednesday, Iran's state-funded broadcaster Press TV reports.
High-profile candidates still in the race include nuclear negotiator Saeed Jalili and former Iranian President Ali Akbar Rafsanjani. Those who've dropped out include former Foreign Ministry Spokesman Ramin Mehmanparast and Davoud Ahmadinejad, incumbent President Mahmoud Ahmadinejad's older brother.
Mahmoud Ahmadinejad is ineligible to compete because of term limits. Rafsanjani has drawn criticism for conservative lawmakers frustrated with his support for former Prime Minister Mir Hossein Mousavi, who ran against Ahmadinejad during 2009 elections.
The formal campaign season begins Friday. Elections are scheduled for June 14. The Guardian Council is tasked with confirming the final election results that will determine the next Iranian president.