The Correction Minister's holding his hands up after mixing up new spending numbers.

The Government's putting up $1.9 billion to add more than 800 beds at Waikeria Prison and deliver 685 more frontline Corrections staff, including 470 prison officers.

Mark Mitchell's office has been forced to issue a correction, after several figures were confused at yesterday's press conference announcing the funding boost.

He says it was his fault.

"I muddied the waters on that, big time. That's on me."

LISTEN ABOVE