Image caption Officials are concerned about mobile phones being smuggled into prisons

Prisoners could soon have telephones fitted inside their cells, the Ministry of Justice has said.

It said it was considering a trial, at one jail, which would allow calls to be made in cells rather than on communal phones on landings.

Officials are concerned about growing numbers of mobile phones being smuggled into prisons.

Harry Fletcher, of the National Association of Probation Officers, said the scheme would need tight controls.

HMP Isis, a young offenders institute in south-east London, is believed to be the front-runner for the pilot scheme.

It houses 622 under-25s within the walls of HMP Belmarsh.

Under the pilot scheme, calls to friends and family will be recorded, as they are currently, but conversations with lawyers will remain private.

A Prison Service spokesman said: "Access to land-line phones for prisoners is normal practice.

"The Prison Service is currently exploring possibilities of a pilot installation in a state-run establishment as we recognise the benefits of such a system.

"Any pilot will be monitored carefully before a decision is made on its roll-out."

Approved numbers

Officials are also concerned about the security issues of prisoners queuing to use public phones.

Mr Fletcher, assistant general secretary of probation union Napo, said that bullying and cajoling was a problem at communal phones on landings.

He said the scheme could "stop the squabble for landing phones every evening" and reduce the staff time supervising it, but he also warned of dangers of abuse.

"There would have to be absolute guarantees that, in private, men are not using the phones to hassle, harass or stalk previous victims, witnesses or partners - there would have to be strong monitoring to ensure that could not happen.

"Authorities should only allow approved numbers, for example six nominated numbers, like solicitor, family, close friends and associates - if not phones are potentially an accessory to a crime," he said.