Southampton boss Nathan Jones wants to add more attacking flair to his squad in order to boost their chances of survival.
Sulemana has been identified as a top target by the Saints and the club are pushing to take him to the south coast of England.
They failed with an initial bid but they returned to the negotiating table with a fresh offer of €20m on Friday.
And according to French sports daily L’Equipe, Rennes are now inching towards the decision to let the winger go in the coming days.
A deal is still not in place but the two clubs have continued to hold talks for the winger’s move to the St. Mary’s Stadium.
Rennes are now considering selling the player and are already preparing for life after Sulemana.
They have already started looking to bring in a replacement in anticipation of the winger leaving.
Southampton are confident that a deal will be done for them to sign Sulemana before Tuesday’s deadline.