The long-serving goalkeeper handed his request to the club's director of football David Pleat on Friday morning. According to Pleat, he 'reluctantly agreed' to accept it.
Walker, 29, has lost his position as first-choice to Scottish international Neil Sullivan. Pleat revealed: "We have reluctantly agreed to a transfer request from Ian Walker. We understand his frustration at his lack of first-team opportunities at the moment.
"It is difficult for him but you have to be patient. This situation was in effect two seasons ago when Espen Baardsen replaced him but he got back in and has done very well since.
"Ian's form last year was excellent and by bringing in Neil Sullivan it increased the competition at the club. We now have two top-class goalkeepers and we are perhaps victims of that situation.
"Ian met me on Friday morning and the players have been informed that we have reluctantly agreed to his request.
"In the meantime Ian will continue to give total commitment to the club. We will be actively looking to find a satisfactory replacement."
Walker made his debut for Spurs against Port Vale in the League Cup almost 10 years ago.
He has since played over 300 games in all competitions for us, lifted the Worthington Cup and won three full England caps.
He actually lost his place to Espen Baardsen back in August 1998 but recovered to win the jersey back just after George Graham's arrival and stayed as number one until the arrival of Sullivan on a Bosman-style free transfer from Wimbledon in the summer.
Ian Walker has asked for a transfer, the Official Spurs Website can exclusively reveal.