Tottenham have had a bid rejected for Lewis Holtby, Schalke have confirmed, as the side look to solve their midfield crisis which was compounded by Sandro's season ending injury.

Holtby turned down interest from the likes of Arsenal and Liverpool to sign for Spurs this month, but under his current agreement with the club he can't leave until his contract runs out in the summer.

But after Sandro was ruled out for the rest of the season as he required knee surgery, Tottenham changed their tune over Holtby, and were hopeful that they might be able to bring the midfielder in earlier to bring more depth to a squad aiming to hold onto their top four spot.

And general manager Horst Heldt says that while the offer has been increased to do the deal now, it isn't enough for the German outfit to consider letting one of their top players go before the summer.

Lewis Holtby
Tottenham made an improved offer to bring Lewis Holtby to the club this month, but it isn't enough.

"Spurs have increased their offer for Holtby, but only slightly. But it is still not acceptable. We have to wait," he said, according to Goal.com. "There's nothing new to add on Holtby or Michel Bastos. We haven't opened talks with Lyon yet.

"Tottenham have only marginally improved their offer for Holtby, but it remains unacceptable for us. We will have to wait to see what happens.

"Feasibility is what it's all about, not wishes."

Schalke manager Lens Keller admitted that there is a possibility Holtby will be a Tottenham player by the end of the month, saying: "Lewis put in a great performance against Hannover. It would be good if he stayed here. But we have to take the financial side into account as well."

Tottenham were also believed to be chasing Mohamed Diame, as the club look to add depth in the middle of the park.