The centre-half has not kicked a ball this term after suffering a knee injury in pre-season but it was hoped he might have been available this month.
"He's on a six-week programme from the medical staff and starting to work now with the fitness coaches," assistant manager Steffen Freund said.
"It's difficult to say now which game he will be back, but hopefully the middle or the end of February.
"He's a really important part of Tottenham. He has a lot of leadership qualities and we are waiting to have him back as quickly as possible.
"He is frustrated. He likes to be involved - especially when you are successful."
On a more positive note, left-back Benoit Assou-Ekotto, who has not played since September, will be involved in Saturday's FA Cup third-round clash against Coventry.