The French midfielder’s Arsenal career has been blighted by injury in recent seasons and he has only made one appearance in all competitions for the Gunners so far this term.
Diaby started his first game in 18 months earlier this season but has spent the rest of the campaign on the sidelines once again.
Recent reports have claimed that Wenger is now prepared to let the 28-year-old leave Emirates Stadium in the summer following another disappointing campaign for the midfielder.
And the Arsenal boss admitted that the midfielder must prove himself on a consistent basis in the coming weeks if he wants to stay at the north London club.
Speaking at a news conference on Thursday morning, Wenger said: “By me, yes [a decision has been taken]. I had a chat with him and told him how I can envisage the future.
“He has to make a decision. Of course he understands completely that he has to perform and to show that he can be present on a consistent way. I will see where we go from there.
“I wouldn’t like to go into details, we have to meet again to see where we go from what I told him. It has to be linked a little bit with his presence.”
Arsenal return to Premier League action when they host Liverpool at Emirates Stadium on Saturday lunchtime.
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