Since protests began on 28 December, at least 50 protesters and 15 security personnel have been killed, according to the US-based Human Rights Activist News Agency (HRANA). More than 2,311 individuals have also been arrested, the group reported.
The Norway-based Iran Human Rights (IHRNGO) said at least 51 protesters, including nine children, had been killed.
BBC Persian has spoken to the families of 22 of them and confirmed their identities.
United Nations Secretary General spokesperson Stéphane Dujarric said the UN was very disturbed by the loss of life.
“People anywhere in the world have a right to demonstrate peacefully, and governments have a responsibility to protect that right and to ensure that that right is respected,” he said.
French President Emmanuel Macron, UK Prime Minister Sir Keir Starmer and German Chancellor Friedrich Merz released a joint statement that said: “The Iranian authorities have the responsibility to protect their own population and must allow for the freedom of expression and peaceful assembly without fear of reprisal.”
Iran’s Supreme Leader Ayatollah Ali Khamenei remained defiant in a televised address on Friday, saying: “The Islamic Republic came to power through the blood of several hundred thousand honourable people and it will not back down in the face of those who deny this.”
Later, in remarks made to a gathering of supporters and broadcast on state television, Khamenei reiterated the message, saying Iran “will not shirk from dealing with destructive elements”.
Iran’s UN ambassador accused the US of “interfering in Iran’s internal affairs through threats, incitement, and the deliberate encouragement of instability and violence,” in a letter to the UN Security Council.