Lewis Holtby will join Tottenham immediately after the club reached an agreement with Schalke.
Holtby has already signed a five-year contract at White Hart Lane but he was not due to join up with his new team until the end of the season when his contract with Schalke expires.
However, with Sandro ruled out for the rest of the season, Spurs enquired about the possibility of bringing the move forward.
Schalke rejected two offers from Spurs for the Germany Under-21 captain with general manager Horst Heldt branding their offers as 'unacceptable' but an agreement has been reached with the 22-year-old set to move to London immediately.
A statement on the Tottenham website read: "We are delighted to announce that we have reached agreement with Schalke for the immediate transfer of Lewis Holtby.
"The Germany Under-21 captain, who had already agreed terms to join the Club this coming summer, has made 27 appearances for the Bundesliga side this season scoring four times.
"Capped on three occasions by the senior German national side, the versatile midfielder joined Schalke in 2009 from Alemannia Aachen and was loaned out to Bochum and Mainz prior to making his breakthrough with the Gelsenkirchen-based club.
"Lewis has made 160 appearances in his career to date, scoring 29 times."