Walker told Sky Sports News: "Luka is a Tottenham player as it stands right now so that's up to Luka, the gaffer and the chairman - whatever they think is the best thing for the club.
"Obviously all the lads think he is a quality player and a valuable player to the team. But like I say, it's not for me to comment on that, it's up to them.
"The chairman made it quite clear we are not a selling club so it was very important he stayed.
"Obviously Scotty (Parker) is sitting mopping up in front of the defence, but Luka is our creative midfielder so it was very important.
"But we have got bags of midfielders, bags of players who can do that - Rafa (van der Vaart), what a player he is. So I think there's strength in depth at Tottenham.
"But like I say, it's the gaffer and chairman's decision and it doesn't matter what I say."