The 22-year-old centre-back has missed four games since he picked up an injury in the Gunners’ penalty shootout defeat in the Europa League to Sporting Lisbon in March.
“He is not progressing as quickly as we had hoped. It is a bit delicate.”
Arteta added: “We want to be very certain when we push him that he is ready to absorb the load and with the risk we would take at the moment that is not possible to do.”
Rob Holding has played in Saliba’s absence and Arteta was asked if he was concerned that the France international, who has made 33 appearances this season, may not feature again this year.
“I don’t know, it’s a bit early to do [predictions]. Probably next week we are going to have more certainty.
“There is some evolution, he is doing more activity, but he is not there yet to start to throw him on the pitch at the level that the sessions demand to compete in this league.”
Arsenal play Southampton at home in the Premier League on Friday night following draws against West Ham and Liverpool, in both of which the Gunners gave up a two-goal lead.