The former United goalkeeper says his fellow Dutchamn called him when he was trying to make a decision on his future and insisted that most of the phone call was spent talking about the Old Trafford club.
"He called me up and said other clubs were in for him, but because I played for two of them, United and Juventus, he wanted to hear my thoughts about them," he told the Daily Telegraph of the ex-Arsenal captain.
"So we spoke for five minutes about Juventus and 55 minutes about United.
"He wanted to know how good United were, what he would find there, how the players are, what Ferguson is like, how they train, how the system works.
"He has shown his quality already. I read a statement from Ryan Giggs, saying that United have signed good players and good talent before, but that this one [Van Persie ] has everything.
"He has the whole package already, but that doesn't always mean it will work of course. Look at Fernando Torres at Chelsea. His first year was difficult, but I think the signs with Robin are good, though."