Although they originally had a rather bitter rivalry on the field, both have mellowed in recent years and now treat each other with more respect than ever.
"We had a few tough periods together but I accept that," Wenger said. "He had the right to decide. He knows it will be more difficult to have that consistency because if the financial power of some teams.
"Did he tell me he was retiring when we spoke about RVP deal? I can't tell you that. I will one day."
Asked how he felt about taking over the title of the Premier League's longest-serving manager, he replied: "It's not a title at all.
"Ferguson is lucky compared to me - he likes horses and golf, so he can have an interesting life again.
"But our job is looking forward to the next game, you are always motivated by that."