Dembele is yet to play for Barcelona this season and is currently locked in a contract stand-off with the Catalan giants.
He is out of contract at the end of the season and Barcelona are in no mood to lose one of their most expensive players on a free transfer next summer.
They have been trying to convince him to sign a new deal but for the moment, there is still no agreement between the club and the player, with Newcastle United in the mix to tempt him away.
According to Spanish daily Mundo Deportivo, Barcelona are not prepared to wait forever for the Frenchman to come to a decision and have set a deadline for the player.
The Catalan giants want Dembele to agree to sign a new contract within the next month or they will take a call on his future.
The club are also employing a softer touch and the entire hierarchy are now in contact with the winger to convince to sign on the dotted line.
But for the moment, no agreement is in place and Dembele has been in talks with Newcastle over a free transfer next summer.
However, Barcelona will try to sell him in January if he does not sign a new contract this winter.