The Hollywood star played the caped crusader in 1997's Batman & Robin while Affleck has played the character in films such as 2016's Batman V Superman.
Clooney himself has previously suggested his turn as Batman wasn't his finest hour, quipping at a Q&A last year: "I did one superhero movie and I f***** it up so bad they won’t let me near the set.”
But he was a bit more confident about it at a recent talk at the Roybal School of Film and Television Production Magnet in Los Angeles.
"If you look at me you just think, 'Oh, he’s just the best Batman of all time'," he said.
The actor's Ocean's Eleven co-star Don Cheadle was also at the event and appeared to tease that Clooney was the "best available".
Clooney then went on: "I mean, Ben Affleck, really?
"No, he’s got nothing on me."
— The Hollywood Reporter (@THR) September 14, 2022
The audience then burst into laughter.
Film fans were also amused by Clooney's remark.
"Good one George," one person tweeted, while another posted: "Love this guy."
"LOL what a good sport," said someone else.
One wrote: "To this day, I still believe there is an awesome Bruce/Batman inside George Clooney."
Someone else said: "Clooney went from apologizing for Batman every chance he got to finally embrace he's the best one. Top tier character development."
Batman has been played by several high-profile actors over the years, including Michael Keaton, Christian Bale and more recently Robert Pattinson.
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