In an exclusive extract of writing smuggled from prison in Iran, the Nobel peace prize laureate Narges Mohammadi has described the “torture” of solitary confinement, and her systematic medical neglect by the prison system.

The writing from the past decade will be part of a soon to be published memoir that gives a rare and alarming insight into the treatment of Mohammadi, who is in critical condition. It details beatings, constant interrogations, deprivation of medical care and long stretches in solitary confinement during her numerous imprisonments.

“There is no hardship worse than illness combined with imprisonment,” she wrote. “Authoritarian regimes do not always need an executioner’s rope. Sometimes, they simply wait for the human body to fail.”

After those words were written and she was rearrested, Mohammadi’s health hit another crisis point this year, with her weight dropping by more than 20kg. She was found unconscious in her cell after an apparent heart attack in March. Requests by her family and doctors for her to receive proper medical treatment from her team of surgeons in Tehran were repeatedly denied. She is now being held at a small regional hospital in Zanjan, in a critical condition.

Her family have said her ongoing detention and the refusal of proper medical care constitute a “slow execution”.

Mohammadi wrote of how her stretches in prison have caused significant damage to her health. She has suffered a pulmonary embolism, seizures, multiple infections, chest pain and other life-threatening medical events in prison, and describes the agonising wait for often inadequate medical care.

The writings were smuggled out by fellow prisoners and visitors during Mohammadi’s time in Iran’s notorious Evin, Qarchak and Zanjan prisons, at considerable risk to their own safety. They had to be rewritten several times over the past decade, after pages or notebooks were discovered and destroyed by prison guards.

The memoir, A Woman Never Stops Fighting, will be published in September. It covers Mohammadi’s early life, the way her parents helped inspire her political convictions, her path into activism, and the many years she spent in prison for public protest.

Mohammadi has been arrested 14 times for her activism on advancing women’s rights in Iran, improving the conditions of prisoners and ending the regime’s use of the death penalty.

She has been sentenced to a total of 44 years in prison and 154 lashes across a number of convictions. The campaigner was awarded the Nobel peace prize while in prison in 2023, during the Women, Life, Freedom protests.

In December 2024, she was released on a temporary sentence suspension after a series of health events, but was violently rearrested a year later and sentenced to years’ more prison time in February this year.

Labour MPs would be wrong to remove Keir Starmer, even though voters have given the party a “real kicking” at the ballot box and people feel “bitterly let down”, the education secretary, Bridget Phillipson, has said.

Phillipson said Labour had been “too gloomy” and had made a mistake in trying to withdraw the winter fuel allowance, after the party lost control of about 40 councils and 1,500 seats at the local elections on Thursday.

However, she said a leadership challenge from the Labour backbencher Catherine West would be “completely wrong”.

West, a former minister, said she would begin collecting the 80 necessary names for a challenge on Monday. She is not widely considered a viable candidate herself but if she triggers a contest then other contenders such as Wes Streeting, Angela Rayner or Ed Miliband could come forward.

A contest in the coming weeks would rule out a return for Andy Burnham, the mayor of Greater Manchester, who is not in parliament. The Guardian reported on Saturday that MPs from Labour’s left are expected to urge Miliband to consider a leadership bid in the coming days.

There are currently about 40 Labour MPs who have said they think Starmer should quit or name a date to go. The latest to add his support to West was Josh Simons, the former Cabinet Office minister, who said Starmer must arrange an orderly transition to a new leader as he had “lost the country” and was incapable of “rising to this moment”. Writing in the Times, he said: “To avoid leadership chaos, senior figures across factions should come together to decide the best way forward.”

Facing a threat to his premiership, Starmer gave an interview to the Observer saying he wanted to serve for 10 years. He has also attempted to refresh his government by bringing back the former prime minister Gordon Brown as an adviser on finance, and Harriet Harman as an adviser on women and girls.

However, those in cabinet with leadership ambitions are weighing whether to attempt to oust him.

Phillipson joined other Starmer loyalists in saying it would be the wrong time to change leader.

Speaking on Sky News, she said: “Friday morning, I felt absolutely sick to the bottom of my stomach about the scale of the defeat that we’d suffered. We got a real kicking from the voters. There’s no escaping that, and we have to reflect seriously on that.”

But she added: “I’ve knocked on doors right across the country and in my own community, as colleagues will have done too and as party members will have done as well.

“And what I heard was not a desire for a leadership contest, for the Labour party to spend more time talking amongst ourselves.

“What I heard loud and clear from voters was their deep sense of frustration that they’d voted for change in 2024, they were hopeful that that change would be delivered and they don’t feel that we as a party or we as a Labour government have delivered what they wanted.”

She told BBC’s Sunday With Laura Kuenssberg: “I’m not going to come on here and say that there aren’t big and serious issues that we have to address.

“We can and we will. But I just do not believe that the message we should take from these elections is that we ought to spend time as a party amongst ourselves, arguing amongst ourselves, fighting amongst ourselves.

“We do need to tell a better story. We do need to deliver faster.”

However, Sharon Graham, the leader of the Unite trade union, a major donor to Labour, said she wanted to see more concrete policies to help working-class voters who had deserted the party.

She said Labour had no right to exist and could become “extinct” unless it changed course.