The west London side, who were relegated from the Premier League in May, are keen to add the England international to their ranks after allowing Loic Remy to join Newcastle United on a season-long loan deal.
The 30-year-old forward previously worked with Redknapp during spells at Bournemouth, Portsmouth, Tottenham and West Ham United.
“He’d make a difference to any team,” Redknapp told a pre-match press conference on Friday.
“But we’re nowhere near doing a deal for Jermain Defoe. That’s the reality of it. He belongs to Tottenham.”
Redknapp added he doesn’t believe Defoe, or another QPR target Scott Parker, would see their chances of a place in England’s World Cup squad affected if they dropped down to the Championship.
“If you’re good enough it doesn’t matter. If you’re playing in this division and playing well, it’s better to be playing than at a club and not playing.
“If Scott stayed at Tottenham, he’s got less chance of getting in the international team. Roy Hodgson knows him. He’s not suddenly going to become a worse player because he’s playing in the Championship.
“He knows exactly what Scott Parker or Jermain Defoe can do. It doesn’t matter if they play in the Championship or the Premier, I don’t think it will affect his decision.”
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