The daughter of the late President Akbar Hashemi Rasfanjani has been sentenced to six months in prison for allegedly "spreading lies against the judiciary", a news agency in Iran reported on Saturday.
Faezeh Hashemi was rumoured to have been handed a prison sentence before a report by the Fars news agency was published, as the country prepares for May's presidential election.
"Again, Faezeh Hashemi has been sentenced to six months' jail because of her critical remarks about the judiciary and the guards," the opposition website Kalemeh said.
She was accused of "anti-state propaganda, spreading lies against the judiciary and the Islamic Revolutionary Guards Corps", he said.
The 55-year-old who protested with others over Iran's disputed 2009 presidential election has faced prison time before.
She served six months in 2011 on charges of propagandising against the ruling system and received a six-month suspended prison sentence in 2014 on charges of slandering top officials.
Meanwhile, Iranian MPs have criticised the arrests of journalists and social media organisers ahead of the presidential election in May, with one directly accusing the elite Revolutionary Guards of being behind the move in a letter published on Saturday.
The arrests in recent days are alleged to have targeted unnamed people who run channels on the popular messaging site Telegram supporting reformists and the moderate government of President Hassan Rouhani.
Rouhani, who will seek re-election on 19 May, has united moderates and reformists with his efforts to improve relations with the West, despite largely failing to win the release of jailed opposition leaders or improve civil rights as he promised during the 2013 campaign.