“Chronically bored” prisoners who have missed out on rehabilitation work behind bars because of coronavirus restrictions could go on to commit more crimes once released, a report suggests.

Chief Inspector of Prisons Charlie Taylor warned that the effect of the “prolonged” measures to contain the pandemic and the “lack of support to reduce reoffending” could have long-term consequences and put the public at risk of “serious harm”.

The report came as a court was told “conditions in prison are the worst that they have been in modern times”.

The inspector’s findings, based on analysis of interviews with 72 men, women and children in six prisons between September 30 and November 5, said the spread of Covid-19 was limited in prisons by a restricted daily regime which included long periods of time locked in cells and, as a result, predictions that thousands of people could die behind bars did not materialise.

But this came at a “heavy cost” to the wellbeing of prisoners, many of whom had been locked in cells for 22.5 hours a day on average for months, Mr Taylor said.

Many likened their daily lives to the 1993 film Groundhog Day starring Bill Murray, with some saying they were “sleeping” away their sentences.

A sense of “hopelessness and helplessness” was becoming ingrained and some were “chronically bored”, Mr Taylor said.

He added: “The cumulative effect of such prolonged and severe restrictions on prisoners’ mental health and wellbeing is profound.

“The lack of support to reduce reoffending and help prisoners address their risk of serious harm to the public does not fill me with hope for the longer term.

“It is likely that prisoners who are released with no support to address their offending behaviour and no access to education or work will struggle to cope, potentially leading to further offending and greater strain on public services.”

The report raised questions as to whether the prison service struck the right balance between battling coronavirus and providing prisoners with enough time out of cells and activities to focus on.

It also urged action to make sure jails were ready to reinstate such programmes as soon as it was safe to do so.

Peter Dawson, director of the Prison Reform Trust charity, said the “suffering and long-term harm” described in the report are “deeper than ever”.

“But the report also shows the building blocks for a better future,” he added.

“Empathy and kindness from many staff have made a real difference, and it will be full active days spent out of the confines of a 9ft by 6ft cell that define recovery in the longer term.”

Mr Taylor said he had heard suggestions that the restrictions, and a subsequent reduction in recorded violent incidents, had made prisons safer.

“Clearly, with so little time out of cell, prisoners had less opportunity to be violent or fight, but this was not the full picture according to those we interviewed.

We know these necessary measures have come at a cost, so we continue to support prisoners with their wellbeing and rehabilitation through vital family contact, education, work and exercise

“Prisoners said that violence, intimidation and bullying had not stopped, but had instead taken other forms.

“The accrual of debt persisted, and some had turned to using drugs and other unhealthy coping strategies as a way of managing their isolation and boredom.”

On Wednesday at Canterbury Crown Court, defence barrister Oliver Kirk described poor prison conditions amid the pandemic as he argued gambling addict Nicole Elkabbas should not be jailed for pretending to have cancer and spending more than £45,000 in donations from well-wishers.

Judge Mark Weekes handed her a two-year-and-nine-month sentence.

The Ministry of Justice said the wellbeing of prisoners has been made a priority and rehabilitation work has been moved into cells where possible.

Prisons minister Lucy Frazer said the action taken had “significantly limited the spread of the virus”, adding: “We know these necessary measures have come at a cost, so we continue to support prisoners with their wellbeing and rehabilitation through vital family contact, education, work and exercise.

“I will consider the report’s findings carefully.”