News of the extended years of imprisonment comes after Mohammadi embarked on a hunger strike.

On Monday, Mohammadi had to be taken to a medical facility due to her poor physical condition and was then returned to custody, the Narges Mohammadi Foundation said.

It described the legal proceedings as a "sham trial."

Mohammadi, who was awarded the Nobel Peace Prize in 2023, was sentenced to an additional six years in prison for conspiracy and one and a half years for propaganda activities, her lawyer Mostafa Nili said on X.

"She has been sentenced to six years in prison for 'gathering and collusion' and one and a half years for propaganda and two-year travel ban," he wrote.

Under Iranian law, jail sentences run concurrently

"Ms Mohammadi stated that she was hospitalized three days ago due to her poor physical condition and was subsequently returned to the detention center," Nili said in quotes published by the Narges Mohammadi Foundation.

"Furthermore, as she began to explain the details of recent events and the manner of her arrest, the phone call was disconnected," Nili was quoted as saying.

The Narges Mohammadi Foundation said that with the new charges, she has now been sentenced to over 44 years in prison throughout her life.

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Mohammadi has campaigned for human rights for decades and was arrested in December by security forces while attending the memorial service of Khosrow Alikordi, a human rights lawyer found dead under disputed circumstances.

She has spent much of the past 20 years in Tehran's notorious Evin prison due to her advocacy in defiance of the Islamic Republic's regime.

Iran has not commented yet on the latest development.

Edited by: Zac Crellin