Both defenders will miss Sunday's final game of the season against Southampton due to injury.
Arteta said this morning: "Jurrien, he had a surgery on Tuesday morning on his ankle. He's been feeling that discomfort for many, many weeks. He's been navigating through the season with that issue, and it needed to be resolved, so he's going to be out for a while.
"And Saliba, he's had something in his hamstring the first half, just before halftime, and again, he's going to be out for a few weeks."
Arteta says Saliba will be missing "for a few weeks", while he offered more detail on Timber.
He said, "We don't know yet. It will depend how the recovery goes. It will be weeks, but we don't know exactly how much. Hopefully, it will be somewhere near the pre-season, if everything goes well, but we don't know yet."
Partey's future?
Arteta was also asked about Thomas Partey's situation. Off contract at the end of June, Sunday could mark the Ghana midfielder's final game in an Arsenal shirt.
He replied: "Well, there's some question marks on a few of them, so we'll have to wait and see. We still have another Premier League match to play on Sunday and after that we have some time to sit down and finalise a few things that have to be done.
"In regards to Thomas, consistency-wise, it’s been his best season. I think the way he's played, performed, his availability has been exceptional and he's a really important player for us."
We have everything we need
Arteta went onto to discuss the season overall, it will mark a third consecutive campaign that Arsenal have finished second on the Premier League table. Arteta is adamant they're making progress as a team.
He said: "We all feel the same way, that we feel that we are capable. It's not just a dream or it's not just something you want to do, it's that we have everything that is needed to do that. And even if you do, there is a lot of things that are going to play a part to win. A lot of things. Performance is going to be, the squad quality, availability is going to be, referees, the schedule, who do you play, when, in what kind of form they are, how many days do you have to recover and then the randomness of football.
"That one I cannot control. I cannot control what can happen in that dressing room to somebody in his personal life that can affect his performance, or something happens or competitors do something like in the history of this league. You have seen it online, boom, they do that, and then there is a lot of randomness there. So things that we can control I guarantee we will do our very best."
Arteta also said: "You need to reset. There are many parts. One of them is that obviously you have to rest. Then you need to be very convinced and aligned of what you want to do to give yourself the best chance to be what you want to be. Then you need to start to feel that feeling in your tummy that you are willing to come back here on day one, fully motivated, fully enthusiastic to go again with the group of players and staff that we have."
Congratulations to Ange
Meanwhile, the Gunners manager was also happy to congratulate Tottenham counterpart Ange Postecoglou after last night's Europa League triumph.
He said, "Just congratulate them. I think they are champions, and when you get to that, you have to do a lot of things right. I think they have gone through a season with again a lot of obstacles and difficulties and they have helped them at the end to manage a beautiful moment.
"So you have to congratulate. This is a sport and I am sure they have done everything in their hands to achieve it and they are very happy."
And on the motivation for the players facing Southampton to end the season, Arteta insists they must show "respect to the competition".
He added, "Because you want to have as many points as possible. You are always here representing this club to win and to play in the man"ner that we want to do. We want to achieve the best defensive record, the golden glove that we are still there to play and finish the season again on a high with a good test and always respecting the competition."