According to her lawyer, Ms Sotoudeh was arrested in June and charged with spying, propaganda and insulting Iran's supreme leader Ayatollah Ali Khamenei before being sentenced in Tehran's revolutionary court.

Human Rights Watch said she has been in Evin prison, a notorious outside Tehran, since June 2018, serving a 5-year sentence that she had received in absentia.

The additional 33 years came just days after Iran appointed a new head of the judiciary - Ebrahim Raisi, a hardline cleric who is a protégé of Ayatollah Ali Khamenei.

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Ms Sotoudeh is well-known for her work representing opposition activists, including women prosecuted for removing their mandatory headscarf, and has been awarded the European Parliament's Sakharov Prize for Freedom of Thought.

Amnesty International said the case against Ms Sotoudeh was an "outrageous injustice".

“It is absolutely shocking that Nasrin Sotoudeh is facing nearly four decades in jail and 148 lashes for her peaceful human rights work, including her defence of women protesting against Iran’s degrading forced hijab (veiling) laws," Philip Luther, Amnesty International’s Middle East and North Africa Research and Advocacy Director, said.

"Nasrin Sotoudeh must be released immediately and unconditionally and this obscene sentence quashed without delay."

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Human Rights Watch added that the sentence "draconian" and "an appalling travesty of justice" in a statement on Tuesday.

“Iranian authorities apparently decided to follow up International Women’s Day by sentencing a well-known and highly regarded women’s human rights defender to an inconceivably draconian sentence,” Michael Page, deputy Middle East director at Human Rights Watch, said.

“Sotoudeh’s sentence is a threat aimed at every human rights advocate in Iran to stop defending human rights.”

The UN investigator on human rights in Iran, Javaid Rehman, raised Ms Sotoudeh’s case at the UN Human Rights Council in Geneva on Monday and said she “was reportedly convicted of charges relating to her work and could face a lengthy prison sentence.”

Prominent Iranian human rights lawyer Nasrin Sotoudeh was already serving a five-year prison sentence for her work. Now Iran's revolutionary court adds an outrageous 33 years to her sentence as well as 148 lashes, all for defending the rights of Iranians. https://t.co/kDWgz4M0DT pic.twitter.com/7bEZQ9buDd — Kenneth Roth (@KenRoth) March 12, 2019

“Worrying patterns of intimidation, arrest, prosecution, and ill-treatment of human rights defenders, lawyers, and labor rights activists signal an increasingly severe state response,” Mr Rehman said.



It's not the first time Ms Sotoudeh has been imprisoned.

She was jailed in 2010 for spreading propaganda and conspiring to harm state security - charges she denied - and was released after serving half of her six-year term.

With Reuters