May 16 is Walters' final day on "The View" and her last day as TV personality. The 84-year-old broadcaster is planning to retire when her time on the show she co-created ends.
The mayor called Walters a "living legend" for over 50 years.
Walters, ever the master of the subtle dig, told De Blasio, "It's very kind. Mayor Bloomberg never did this for me."
De Blasio replied, "Times are changing."
Walters got a standing ovation, something she didn't seem comfortable with, and was eager to turn the conversation back to De Blasio.
Walters' last broadcast will come one day after all 11 current and former "View" co-hosts will assemble on the stage for the very first time.