The director general of the Prison Service has denied he is "threatening" prison officers with privatisation of Irish jails in a bid to negotiate new work practices.
The officers are currently in negotiations with the management of the Prison Service in a bid to tackle the serious financial problem and to cut the cost of overtime.
The bill for prison officer overtime has reached €64 million, or a third of the annual wage bill. It was reported last year that some prison officers were earning more than a prison governor due to their long overtime hours.
In an interview on RTE's News at Oneprogramme today, Mr Sean Aylward, director general of the Prison Service, denied media reports that he had threatened prison officers with privatisation of prisons if they failed to reach agreement on the issues under discussion.
Mr Aylward said that when the question was put to him by prison officers, he had said he could not exclude options that would include privatisation if no agreement was reached on cost structures going forward.
"It would be folly for someone in a management position like mine to assume that we were going to go forward under the present cost structure. It's not sustainable," he said.
He said prison officers were failing to work "smartly" by adopting new technology which would reduce the need for overtime.
Discussing the systems in operation in some other countries, Mr Aylward said custodial service in some prisons is managed under "very strong controls" by a private management firm. He added that this did not mean the prison was just "handed over" and that people are just "punishment for profit". He said it was very important that people are punished in accordance with law and that the State controls the prisons.
Speaking on the same programme, Mr Gabriel Keaveney, president of the Irish Prison Officers Association, said prison officers were being "conscripted" and compelled to do overtime. Mr Aylward said this was because of their refusal to use new technology in some prisons.
Mr Keaveney accused the Prison Service director general of "bully boy tactics" and objected to any move towards a "US-style" prison system where prisons were nothing more than "criminal universities".
On the separate issue of the proposed smoking ban in all workplaces next year, Mr Aylward said he favoured a "rolling ban". He said it was asking "a touch too much" for prisoners to be forced into an outright ban from January.