Manchester United manager Louis van Gaal has refused to rule out the possibility of signing goalkeeper Victor Valdes.
Manchester City boss Manuel Pellegrini says he is confident that England goalkeeper Joe Hart will sign a new contract.
Pritchard, 20, a reported target for Liverpool recently, has impressed for Spurs' youth and reserve sides but has yet to make a first-team appearance for the Barclays Premier League club.
Posh chairman Darragh MacAnthony said via Twitter: "Delighted to announce loan signing of Alex Pritchard from Spurs who has joined until end of season. He is a fantastic young talent.
"Myself & Gaffer watched this young lad destroy our reserve team couple weeks ago scoring 4 goals from playing left wing / right wing / attacking midfield."