News emerged earlier that Rangers had moved quickly to snatch the 29-year-old playmaker, who has failed to secure a regular place in Spurs' first team.
While the South African player seems to be out of favour at White Hart Lane, it is understood that the North London club have rejected an offer from Mark Hughes, according to Sky Sports News.
Speaking in a press conference this morning before QPR tabled their bid, Redknapp said: "I wouldn't want to let [Pienaar] go if I can help it. I want to keep Steven, he's a good player.
"I don't have any need to weaken the squad, I'd rather have a good squad around me for these last 18 games than letting one or two go because you never know when you run into injuries. Steven is a good player, there's no-one here really that I could sit and say I'd love to see the back of."
Meanwhile, the Spurs boss has hinted that the club will not hijack Chelsea's bid for Gary Cahill.