In a surprising twist of events, reports emerged on Thursday that Erik Ten Hag's side, who will be playing Europa League football this season, are willing to offer Real Madrid an initial €60m transfer fee for Casemiro.
The 30-year-old Brazilian defensive midfielder is being offered a four-year contract with the option of a further year and is keen to try a new challenge after spending close to a decade on the books of Real Madrid.
Casemiro joined Real Madrid from Sao Paulo in January 2013 and became a mainstay in the Los Blancos midfield after spending the 2014/2015 season on loan at FC Porto.
Casemiro won five UEFA Champions League trophies with Real Madrid, three La Liga titles, one Copa del Rey, three FIFA Club World Cups and was named man-of-the-match last week when winning the UEFA Super Cup for a third time as Ancelotti's side defeated Eintracht Frankfurt 2-0 in Helsinki.
Speaking ahead of Real Madrid's weekend game against Celta Vigo, Ancelotti told reporters: "We've spoken this morning, he wants to try a new challenge, a new opportunity. I understand this, also the club does.
"Because of what he has done in this club, his desire and due to everything he has done for this team, we need to be respectful of this.
"There are negotiations between the clubs, he is still a Real Madrid player but it looks like he is now willing to depart. If he is departing we have a lot of resources to replace him."
Asked if he had attempted to sway Casemiro's decision to leave, Ancelotti replied: "No.
"I've always talked a lot with him in my second time at Real Madrid. I just listened to his desire, I think there's no turning back. This is what he wants.
"If everything goes well, the negotiations go well, we just need to wish him the very best.
"It is difficult to speak anyway because I don't know what's going to happen in the next few hours, if he's staying or leaving, but if he leaves we will always be thankful to him because he's been a wonderful player with us."
