The Rs manager is keen to bolster his midfield as they prepare for their return to the Premier League, with the pursuit of the Netherlands international and other targets "ongoing"
The Netherlands international, who played for this country at the World Cup, only joined the Canaries from FC Twenty last summer but was unable to prevent the club from relegation to the Championship in May.
Redknapp is now looking to offer Fer another crack in the Premier League, although he is unsure how close a deal is to completion.
"[Fer] is a player we like but I don't know where that one is at the moment," he told Sky Sports News.
"It's been ongoing for a while but there are other people as well that we are looking at.
"I think we need a couple of midfield players and we have got other targets we are looking at.
"We need to strengthen in a few positions really to be strong enough to really have a go at it this year."