As revealed by Goal on Thursday, the Frenchman is set to return to the Gunners squad for the trip to Old Trafford after missing a number of games with a groin injury.
Jack Wilshere will also train ahead of the clash, with the manager telling reporters: "Flamini and Wilshere will join in the training session."
|11/5||Arsenal are 11/5 with Bet365 to claim victory at Man Utd this Sunday
The Gunners head into Sunday's match five points clear at the top of the Premier League table, and eight points ahead of opponents United.
The 64-year-old is targeting the clash as another confidence booster - after their recent 1-0 win away against Dortmund - but admits facing a manager other than Sir Alex Ferguson in the Old Trafford dugout will be odd.
"It is one of the games where you can build confidence and gain credit," he continued. "Recently we have not done so well there.
"It will be a bit strange without Sir Alex Ferguson there on Sunday. It's too early to tell the difference under Moyes. He has shown great competence at Everton."
Arsenal have been praised for their defensive improvements this season, something that was evident in that 1-0 victory over Dortmund, but the boss isn't satisfied just yet.
"We have made a lot of improvements at the back - but there is a lot to do," he added.
"[Per] Mertesacker and [Laurent] Koscielny complement each other well - the team help them as well."
Meanwhile, Goal can also reveal that Lukas Podolski is set to make a return from his long-term "horror" hamstring injury in December, having been unavailable since August.