Bluebirds chairman Peter Ridsdale has every confidence that Ramsey will make the correct decision after the trio all agreed a £5million fee for the highly-rated 17-year-old.
Ridsdale said in the News of the World: "I spoke to Aaron on Friday night.
"He told me he'd had a great day at United and was on his way to see Arsene. After that, the final decision is up to the boy.
"Aaron spoke to Sir Alex Ferguson before visiting United. He's a sensible lad and will listen to what Arsene has to say."