The defender joined the Gunners last summer for a fee of around £27million, but he was loaned back to Saint-Etienne for the season.
Ligue 1 was cancelled in April due to the coronavirus pandemic, but the Coupe de France final between Saint-Etienne and Paris-Saint Germain has been rescheduled for July 24.
That creates a problem for Saint-Etienne as Saliba's loan deal with them is due to expire on June 30.
“I think he needs to stay there. We've got an agreement with Saint-Etienne, he's been over there all year," Arteta said.
“He has earned the right to play in that final if the manager wants to do that. I think we have to give him the opportunity to do that, to enjoy that and we can have him after that.
“I spoke with him a few times. He has been around a few times here as well. We have been following his season.
“As a young player, he had a difficult season with injuries that he had but it is part of his process.
“I know how high the expectations are on him for next year but we have to bear in mind the age that he's at and what he has done in the past, and make sure we create the right environment for him so he can keep going as a player."