The attacking midfielder has lost his place as an undisputed first-team player in the side since his move to Galatasaray and national team coach Louis van Gaal recently hinted that Sneijder's place in the World Cup squad is under threat.
Nevertheless, Robben feels the former Inter star still has plenty to offer, telling NOS: "Wesley Sneijder is a very important player. I have already said this before and it's not a secret how I feel about Wesley. When he plays at his own level and is fully match fit, which he is now, Wesley is a player who brings something extra. You need that at a World Cup.
"Wesley is an extraordinary player when he's at his best and we have to take advantage of that. I am a fan of Wesley. Of course, we shouldn't compare him to the player he was four years ago. We've moved on and things have changed since then. But he still adds something to Oranje."
Sneijder has made 97 appearances for Netherlands so far, scoring 26 goals in the process.