Mojtaba Kabiri, the head of the Department for Passport and Visa Affairs at the Foreign Ministry, said more than two million visas were issued to Iranian nationals who intended to take part in the annual Arbaeen ceremony in Iraq this year.
He added that last year, nearly 1.6 million visas had been issued to Iranians going on pilgrimage to holy cities in Iraq.
Arbaeen, which is the largest religious gathering in the world, comes 40 days after Ashura, the martyrdom anniversary of the third Shiite Imam, Imam Hussein (AS).
Each year, a huge crowd of Shiites flock to the Iraqi city of Karbala, where the holy shrine of Imam Hussein (AS) is located, to perform mourning rites.
Last year, around 20 million pilgrims from all over the world, including over 1.6 million Iranians, gathered in Karbala to attend the mourning ceremonies marking Arbaeen.