The Hollywood actor and singer said he had “absolutely no ill will” against the King, but that breaking away from the UK monarchy seemed like a “natural part of an evolution of a country”.
Speaking on Sunday with Laura Kuenssberg, he revealed he held dual-British and Australian citizenship and that he had grown up in a household that celebrated the royals.
“I think Australia will become Republican at some point. It feels natural,” he said.
“It feels like something that is, I would guess inevitable, and I guess would be a natural part of an evolution of a country. You know?”
He continued: “I’m a British citizen as I am an Australian citizen – I don’t know if people know that but I am… my father made us stop doing whatever we could to watch in 1981 the wedding of Lady Di and Prince Charles. We had champagne.
“So I grew up with a lot of that. There was no bunting in our house, but if my dad could have found that there would have been bunting and I have absolutely no ill will and I only wish King Charles all the best.”
He added that he “really appreciated” the service of both the King and late-Queen, whom he had met on several occasions.
“I admire it and I only wish them the best,” he said.
Asked again if he thought Australia would “go its own way”, he replied: “I think it’s inevitable at some point.”