Iranian authorities organised a demonstration against Saudi Arabia's management of the annual hajj on Friday as it mourned 131 nationals among 717 pilgrims killed in a crush outside Mecca.
Iranian leaders have been deeply critical of the Saudi authorities over what they charge were flawed safety measures that led to Thursday's tragedy.
"Saudi Arabia is incapable of organising the pilgrimage," said Ayatollah Mohammad Emami Kashani, leading the main weekly Muslim prayers in Tehran.
"The running of the hajj must be handed over to Islamic states."
After the prayers, worshippers held a protest against the "mischievous and incompetent regime" in Riyadh, said the Islamic Propagation Coordination Council which organises state-sponsored demonstrations in Iran.
Thursday's loss of life was the biggest to hit the annual Muslim pilgrimage in a quarter-century and came just weeks after a crane collapse in the holy city of Mecca killed more than 100 pilgrims, many of them foreigners.
Iran's supreme leader Ayatollah Ali Khamenei blamed "improper measures" and "mismanagement" by Saudi authorities, who he said "must accept the huge responsibility for this catastrophe".
Shiite Iran and Sunni Saudi Arabia are bitter rivals whose relations are already strained by regional conflicts from Syria to Yemen.
The custodianship of the Muslim holy places forms a key plank in the Saudi monarchy's claims to legitimacy.