UN experts and 400 prominent women have urged Iran not to execute Zahra Tabari, a 67-year-old electrical engineer and women's rights activist.
Ms Tabari was arrested in April and accused of collaborating with a banned opposition group, the People's Mujahideen Organisation of Iran (PMOI), according to her family.
In October, she was convicted of "armed rebellion" by a Revolutionary Court in Rasht after a trial via video link that lasted less than 10 minutes. Her family said the verdict was based on extremely limited and unreliable evidence: a piece of cloth bearing the words "Woman, Resistance, Freedom", and an unpublished audio message.
Iranian authorities have not yet commented on the case.
At least 51 other people are known to be facing the death penalty in Iran after being convicted of national security offences including armed rebellion, as well as "enmity against God", "corruption on Earth" and espionage, according to the UN experts.
