Under the terms of his move to the Nou Camp back in 2011, the Gunners could be offered the chance of re-signing the Spaniard for as little as £20million should Manchester United, who are keen on signing the former Arsenal captain, formalise their interest.
"I think at the moment he's lacking the confidence of being a regular player," Wenger told Al Jazeera. "Recently he has not been that.
"Cesc is such a passionate player, a player of such quality, that it must hurt him not to play in every single game. That's what he misses. When you come in and out you never play with full confidence."