Mustafi has insisted Ozil is still putting 100 percent effort into training sessions despite being frozen out by Mikel Arteta.
The German midfielder has not made an appearance since March and has been left out of the Gunners' Premier League and Europa League squads.
When asked about Ozil's situation, Mustafi replied: "I can't say too much about it. They have been talking a lot about it.
"For me, Mesut is not just a team-mate, he's a friend. I respect him and he has always respected me and everyone else as far as I have seen.
"He will always have my respect and I will always be there for him if he needs something to motivate and push him.
"But at the moment every time I see him in training he's doing the best he can.
"He tries to train well and everything else is not in my hands. I'm not the one who makes the decisions."