"Death to the dictator": Iranians took to the streets in large numbers to defy the power of Ayatollah Ali Khamenei, according to videos verified by AFP on Friday, with Paris calling on the authorities to show "restraint".

The internet, which was cut off across the country on Thursday, remained inaccessible, according to the cybersecurity monitoring NGO Netblocks.

Iran "has now been disconnected for 12 hours," the organization wrote on its X account, "in an attempt to stifle the wave of protest."

Images show crowds of people demonstrating on several avenues in Tehran, chanting "death to the dictator," referring to Supreme Leader Ayatollah Ali Khamenei, who has ruled the Islamic Republic since 1989.

Other videos show large demonstrations in several cities across the country, including Tabriz (north), the holy city of Mashhad (east) and the predominantly Kurdish west of the country, particularly around the large city of Kermanshah.

In several images that AFP has not been able to authenticate at this stage, protesters can be seen setting fire to the entrance of the regional branch of state television in the city of Isfahan (central).

Flames were also visible inside the governorate building in Shazand, central Iran, after protesters gathered outside, according to other videos.

The son of the former Shah and leading opposition figure in exile, Reza Pahlavi, urged on Friday a new show of force in the streets in order to amplify the mobilization and "further weaken the repressive power of the regime".

These demonstrations are the largest in Iran since those that occurred after the death in 2022 of Mahsa Amini, who was arrested for allegedly wearing a poorly fitted headscarf.

Human rights organizations have accused the authorities of opening fire on protesters, killing dozens since the protests began in late December, initially against the high cost of living.

France, saying it understands "the legitimate aspirations of the Iranian people", called on Iranian authorities on Friday "to exercise maximum restraint" in their response to the protests, according to a diplomatic source.

The day before, Berlin had denounced an "excessive use of force" by the Iranian authorities "against peaceful protesters", and urged the authorities in Tehran to "respect their international obligations" in this matter.