Iranians took to the streets in new protests Friday to press the biggest movement against the Islamic republic in more than three years, as authorities sustained an internet blackout as part of a crackdown that has left dozens dead.

Protests have taken place across Iran for 13 days in a movement sparked by anger over the rising cost of living that is now marked by calls for the end of the clerical system that has ruled Iran since the 1979 Islamic revolution which ousted the pro-Western shah.

In Tehran's Sadatabad district, people banged pots and chanted anti-government slogans including "death to Khamenei", in reference to supreme leader Ayatollah Ali Khamenei, as cars hooted in support, a video verified by AFP showed.

Other social media images showed similar protests elsewhere in Tehran, while videos published by Persian language television channels based outside Iran showed large numbers taking part in new protests in the eastern city of Mashhad, Tabriz in the north and the holy city of Qom.

These protests followed giant demonstrations on Thursday that were the biggest in Iran since the 2022-2023 protest movement sparked by the custody death of Mahsa Amini, who had been arrested for allegedly violating the dress rules for women.