The England international has regularly featured for Redknapp during his career, enjoying spells at the likes of West Ham, Portsmouth and Tottenham.
Defoe left Spurs for MLS side Toronto early this year - registering 11 goals in 19 league appearances for his new club - and has been linked with a return to the Premier League with QPR.
Redknapp confirmed there had been no movement on a bid since a failed attempt to sign the 32-year-old in the close-season but strongly hinted at a potential move in the new year.
"I don't think anything is anywhere near being concluded," said Redknapp.
"Tony [Fernandes] the chairman is away, we tried to get Jermain before the deadline [but] I don't think there's any movement on that one.
"He's a player that certainly I'm sure we'd be interested in in January but it depends on the expense of it all and what the deal is really. Only Tony will deal with that so it's up to him.
"I'm a big fan of his, I've signed him enough times. He's a goalscorer and he's obviously a player you would like at your club if possible but the figures would have to be right and everything.
"I haven't spoken to Tony about that yet."
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