The Netherlands international striker is set to seal a £24 million switch to the Red Devils and may move in time to make his debut on Monday in their Premier League opener against Everton.
|13/2||Robin van Persie is 13/2 to score two or more goals against Everton
While the player travels to Manchester to discuss terms and undergo a medical, Goal.com exclusively revealed the astonishing £73m package that United used to entice the Gunners skipper to Old Trafford.
Wenger revealed he was frustrated to lose the 29-year-old to a division rival and admitted he would have rather sold him to a foreign club.
Wenger told French TV station TF1: "We made our rivals stronger, this is what we wanted to avoid at all costs, but we have not.
"Honestly, I would have preferred the sell abroad, for example, PSG rather than Manchester United. They have the advantage of having played against him and know his great class and value.
"He really is an exceptional player in the pure sense of the term. I have not known many players in my life who have this quality of first touch and this intelligence of movement.
"Unfortunately, we have the reality, the economic reality, and the reality of the desire of the player. When you are not able to extend a player and that he is in his last year of contract there was no other way than to let him go.
"It's sad because he's a player who has played for eight years at Arsenal, and unfortunately it is an another pill to swallow. We have swallowed a lot, we have always survived. It is a real challenge to meet."
Wenger admitted it would be difficult to replace the Dutchman but called upon his summer signings, Olivier Giroud and Lukas Podolski to replace Van Persie's goals.
He added: "This is a player who has scored 30 goals in the Premier League last year, he scored virtually in all games. So it will be a challenge for our attackers to replace him.
"The economic point is the only point of satisfaction. But you do not play with the money on the pitch, you play with the quality of the players. When we lose a player like that, it is always very difficult.
It will give more chance to Giroud, because when Van Persie is there honestly he is the first that you put on the sheet and then you put the others around. So, there is certainly a vacuum to fill, it's down to the ones who can seize the chance."