Relatives of jailed Iranian human rights campaigner Narges Mohammadi and the Nobel Peace Prize Committee have called for her to be transferred to adequate medical facilities following a sharp reported deterioration of her health.

On Friday her family said the 54-year-old had been taken from her prison in north-west Iran to a local hospital, calling the move a "last-minute" action that may come too late.

Her brother, who lives in Norway, told the BBC on Saturday: "Her blood pressure has dropped sharply, and they haven't been able to stabilise it."

Narges Mohammadi was awarded the 2023 Nobel Peace Prize. She was arrested in December for her criticism of the authorities.

Last month her brother Hamidreza Mohammadi said she had been found unconscious by fellow inmates at Zanjan Prison in north-west Iran, after suffering a suspected heart attack.

He added that prison officials had refused to transfer her to a hospital despite her history of cardiac, lung and blood pressure problems.

On Friday, the Narges Mohammadi Foundation, run by her family, said she had been transferred to a hospital in Zanjan province "following a catastrophic deterioration in her health".

The statement added that it came "after 140 days of arbitrary detention and the persistent denial of specialised healthcare".

On Saturday, Hamidreza Mohammadi told the BBC: "Her current problems include low blood pressure and a heart attack, but her previous conditions, such as pulmonary embolism (…) and having undergone stenting and angiography, make any treatment by the doctors in Zanjan effectively impossible."

He said his sister should be transferred to a hospital in Tehran "so that her own specialists, who have treated her previously, can take over her care".

The call was echoed by Jorgen Watne Frydnes, head of the Nobel Peace Prize committee, who told Reuters news agency that Mohammadi's life remained at risk.

Over her lifetime, she has been arrested 13 times and been sentenced to a total of 31 years in prison and 154 lashes, according to her foundation.

In 2021, she began serving a 13-year sentence on charges of committing "propaganda activity against the state" and "collusion against state security", which she denied.

In December 2024, she was given a temporary release from Tehran's notorious Evin prison on medical grounds.

She continued campaigning while undergoing treatment and was arrested in the north-eastern city of Mashhad last December after giving a speech at the memorial ceremony of a fellow human rights activist. Her family said she was taken to hospital after being beaten during the arrest.

In early February, Mohammadi was sentenced by a Revolutionary Court to an additional seven-and-a-half years in prison after being convicted of "gathering and collusion" and "propaganda activities", her lawyer said.

She was transferred without warning the following week to Zanjan prison and has been allowed only limited communication with her family since then.