The arrival of the 23 year old has also seen the temporary departure of Djimi Traore. The ex-Liverpool defender has signed for French club Rennes until the end of the season, with the option of a permanent deal in the summer.
Pompey boss Harry Redknapp told the club's official website: "He's big, strong and quick. I watched him several times.
"He can play left-back, down the left-side and centre-half. I thought he would be an interesting loan."