UPDATED 3.06pm: The boss of the privately managed new prison in South Auckland says their operation will be strictly monitored by the Government.

The 960-bed corrections facility in Wiri is now ready to take in male prisoners.

Serco Chief Executive Mark Irwin says if they don't meet their security and prisoner rehabilitation targets they will face penalties.

"There are absolutely strict perform criteria. Not only with regard to reoffending, but many other areas such as loss of control, deaths in custody - $150,000 in that case."

Meanwhile, Corrections is confident it's got the right people in place to manage the country's newest private prison.

The Corrections Minister says he's confident Circo is the right firm to manage the country's prison in South Auckland despite concerns raised overseas.

Sam Lotu Iiga also defended the move to provide phones and computer in prison cells.

He says it's a learning tool to rehabilitate prisoners and educate them when they leave the facility.