The France international, 28, was provisionally ruled out until next year after breaking his leg against Everton in August, but he is now ready to return.
“He is three or four weeks ahead of schedule,” manager Arsene Wenger told the club website. “Originally we planned to have him back for competition at the beginning of next year. So he’s one month ahead.”
Mikel Arteta has also returned to fitness after a hamstring problem, but Wenger said that Laurent Koscielny (Achilles) and Mathieu Debuchy (ankle) were both around “three weeks away from full group training”.
German playmaker Mesut Ozil (knee) and back-up goalkeeper David Ospina (thigh) remain long-term absentees.