The centre-back missed the Gunners' first match of the Premier League season against Leicester last weekend.
But he is in contention to play at Stoke tomorrow.
Arsenal have rejected the loan approach from Inter but Sky Sports say the Serie A side will now return with a bid for a permanent transfer.
The Gunners are said to want £35m for the Germany international in order to recoup the money they paid for him just last summer.
Mustafi made 26 top flight appearances for Arsenal last season and was first-choice alongside Laurent Koscielny.
Arsene Wenger will be keen to keep hold of the 25-year-old as he looks for his first Premier League title since 2004.
Arsenal are not blessed in central defence with Per Mertesacker set to retire at the end of the season, Rob Holding still proving himself at the top level and Calum Chambers yet to make an impact.
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And ex-Gunners star Paul Merson would certainly be against the transfer as he thinks the club must strengthen.
He said on Sky Sports: "No I don’t (see any improvement). I don’t see where the improvement is going to come from.
"There’s a saying in everything in life: if you keep on doing the same things, you will get the same results.
"They haven’t bought anybody in that’s going to make me change my mind."
