Cunningham is a Republic of Ireland international
Nottingham Forest have agreed a deal to extend defender Greg Cunningham's loan from Manchester City until the end of the season.
The left-back has made 10 appearances for the struggling Reds since joining from City in October.
Boss Steve Cotterill told the club website
: "I think he has done really well and has caught everyone's eye.
He's a really good footballer and a fantastic lad - he has fitted in around the place very well."
The 20-year-old's deal was due to end after Saturday's match against Cardiff.
Forest currently sit third from bottom of the Championship.