Portsmouth encourage Man City to bid for Kaboul
Pompey executive director Mark Jacobs said: "It just depends on what happens, basically.
"If another club makes a silly offer for some of our players, which quite clearly they can, then there’s not that many people available in the January transfer window, as everyone knows.
"Those that are available take a bigger premium."
Kaboul, 23, has played 34 games - scoring four goals - since arriving at Fratton Park from Spurs in July 2007 in a £7million deal.