Kaboul is expected to leave White Hart Lane during the summer after struggling to establish himself at Spurs last season.

His agent has ruled out a move to Sunderland, but Portsmouth have been mooted as favourites to sign the France Under 21 international.

Redknapp is willing to take the defender to Fratton Park, but is reluctant to pay over the odds for any player.

"I like him, Kaboul," Redknapp told Sky Sports News. "He's a young player I tried to sign before and I'm interested, but the price has got to be right.

"We can't be paying over the top, you've got to pay what you consider to be a fair price for players.

"I think clubs, like us, need to do a deal where if you go and play games and they're successful, great, you pay the money.

"If players come and they don't do the business, I think you've got to be more creative with doing transfers.

"If they're successful you don't mind paying. That's the type of deal we need to do with one or two players - pay a decent up front fee and more money if they're successful and more money if you sell them on, that type of deal."