Schalke have rejected Tottenham's request to fast track Lewis Holtby's contract with the Premier League club, claiming Spurs made an "unacceptable" offer for the midfielder.
Holtby, 22, has agreed to move to White Hart Lane in the summer, but Tottenham have attempted to secure the German this month in a bid to boost their hopes of Champions League football next season.
With Brazilian midfielder Sandro ruled out for the rest of the season with a knee injury, Spurs were hoping to reach a new agreement with the Bundesliga side, but Schalke manager Horst Heldt has confirmed Holtby will remain in Germany until June.
"Tottenham have made an offer, which was not acceptable, therefore it was rejected," he said. "The transfer window is still open and Lewis has not become any cheaper."
Holtby created two goals and scored what proved to be the match winner in Schalke's 5-4 win over Hannover 96 on Saturday, with the Germany Under-21 captain insisting he will see out his contract at the Veltins Arena.
"I am not going to just leave without busting my arse for the team," Holtby said. "I will give my all for Schalke until the last second. Everything else must be decided by the clubs."