Clubs have until Friday to sign Lyon duo Houssem Aouar and Memphis Depay, according to club president Jean-Michel Aulas.
Aouar, 22, has been linked with a move to Arsenal, with Lyon demanding at least €60m for the French midfielder.
"We will tell the players that whatever will not be settled in terms of departures before Friday, there will be no more departures," Aulas told Telefoot.
"So for us the [closing] date of the transfer window will be Friday. I think I will propose it tomorrow (Tuesday) to Rudi Garcia and Juninho, because it's understandable.
"And all people of goodwill can see that there is something wrong [with the results of the team]. It can be because of that, but it can also be a lot of other things. In any case, from Friday, the players who have not left will not leave."