Wandsworth Prison is one of 30 acoss southern England which are "run-down and poorly-located" and should be replaced by 12 "super-jails", a report has claimed.

The author, former prison governor Kevin Lockyer, argued the move would save £600m a year in operational costs.

He said super-prisons, which would contain up to 3,000 inmates, would not only save money but lead to a reduction in reoffending rates and a better quality of life for prisoners and prison staff.

But the Prison Reform Trust, who campaign for improvements to the service, said it would be a "gigantic mistake" to spend money on a series of super-sized jails.

Prison Reform Trust director Juliet Lyon said: "With crime falling and community sentences and treatment to tackle addictions working to reduce reoffending, it would be a gigantic mistake to pour taxpayers' money down a super-sized, big brother prison-building drain.

"There is scope to close some outdated prisons and reinvest the money saved into effective community solutions to crime."

In the report, published by right-wing think tank Policy Exchange, Mr Lockyer writes: "Wandsworth is large, but it is also overcrowded (with a certified normal accommodation around 500 places fewer than its operating capacity), old and on a cramped site which is difficult to adapt.

"Wandsworth is a difficult prison to manage and outcomes for prisoners, as
assessed by the Inspectorate, are mixed.

"But it is a difficult prison because of its age and its unsuitability to the tasks now being asked of it, not because of its size."

Wandsworth has a 'normal' capacity of 1,107 inmates and it spends just under £46m a year, which is about £41,000 per inmate.

The Prison Inspectorate’s report, on an inspection of Wandsworth Prison in 2011, found that “the treatment and conditions of simply too many prisoners at Wandsworth was demeaning, unsafe and fell below what could be classed as decent.”

And today's report adds: "We have focused on London and the South West region to illustrate the kind of changes to the estate we need.

"For example, in London, we are recommending the closure of HMP Brixton, HMP Feltham, HMP Holloway, HMP Pentonville, HMP Wandsworth and HMP Wormwood Scrubs.

"We then propose the construction of three 2500 place prisons within the M25, on brownfield sites, to provide: 500 places for women, to replace Holloway; 1000 places for young adults to replace the young offender capacity at Feltham; and 6000 places to replace the adult male capacity lost by the proposed closures and provide additional space to reduce movement of prisoners from London to other regions.”

The report is available to read on Policy Exchange's website.