Spurs bought the England Under-20 international from the Blades last summer, along with fellow full-back Kyle Naughton who left White Hart Lane for a loan spell at Middlesbrough on Monday, with Walker returning to Bramall Lane for the season.
According to the Coca-Cola Championship club's official website, Spurs contacted them 50 minutes before Monday's 5pm transfer deadline to exercise their right to recall the Sheffield-born player.
Although Blades staff attempted to dissuade Spurs it was to no avail and Walker returned to White Hart Lane.
The 19-year-old has been a stand-out performer for the Blades this year and an integral member of the squad who are pushing for promotion. Walker has made 28 appearances back in South Yorkshire including two in the FA Cup meaning he would be cup-tied for the remainder of Spurs' cup campaign.
Source: PA
Source: PA