Wenger finds amusement in talk of Arsenal signing van Nistelrooy.
Van Nistelrooy has been mentioned as a possible January transfer target for Wenger as he looks to bring in a new striker to compensate for the loss of Robin van Persie to long-term injury.
The Frenchman admits any move is highly unlikely considering van Nistelrooy's popularity among Arsenal fans following a number of high-profile incidents during games between the Gunners and United.
Asked about his pursuit of a striker and the chances of signing van Nistelrooy, Wenger said: "It would not be the best of starts, bearing in mind our past relationship! You have my number - you can text me all the names you find!"
Wenger also played down Arsenal chances of brining in a new forward during the January transfer window as he accepts his options are limited.
"We're at the beginning of December, if we are in the same situation with injuries in January then I will see," added Wenger.
"But we can't dream too much of finding a world class player because that's what is needed to strengthen our team.
"But they also need not to be European cup-tied and who is also free so we must hope Father Christmas is good to us!"