Reports had linked the 107-capped former England international with a move to the Championship club and Redknapp feels that despite Cole's advanced age he would still be a major asset to a club chasing Premier League promotion.
“Ashley Cole is still in great nick,” the manager said, as quoted by the Birmingham Mail.
“Someone mentioned him and I thought 'that's an interesting player, for sure'. You can't beat a bit of quality.
“For me, he was probably the best left-back in the world when he was at Chelsea. I know Ashley, he's a great lad and he could certainly play at this level – no problem.
“[Birmingham's interest] hasn't really gone anywhere though. I just mentioned it to someone and like everything it ends up getting out.”
Cole, who currently turns out for MLS side LA Galaxy after having managed only 11 Serie A appearances during his two seasons at Roma, remains one of the most decorated defenders of his era, boasting a Champions League title, four Premier League titles and seven FA Cups.
And, understandably, Redknapp feels the full-back's experience would be a massive boost in particular to the younger players within his current squad.
“I think if you get a few [experienced players] in your club they are better than any coach with the young players,” he said.
“People look at them and see how they are, how they train and perform every day, see what has made them great players - and it rubs off.
“I am all for having two or three great senior players around if I can find the right ones to come and play in the team.
“It worked for me before so there is no reason why it can’t work for me here if I get the right ones in.”