The 60-year-old actor, who currently lives near San Francisco with wife Susan Schneider, revealed that he enjoys travelling around with his pet.
"I've done the ranch thing, now I'm doing the water thing where I go kayaking and paddleboarding and take to the woods for hours on my bike," he told the Irish Independent. "It's my thinking time and very therapeutic.
"I also have a gay rescue pug called Leonard, who I take for walks because I am very secure in my sexuality. He has a boyfriend and they are planning to adopt a Siamese kitten together. We're very modern."
He also revealed that he has no plans to star in any reality television series, saying: "I've never been asked to appear on I'm a Celebrity . . . Get Me Out of Here! so I guess I mustn't be on the professional skids just yet. Besides, I would never appear on it. I don't do well with snakes and I can't dance.
"I am such a bad dancer, in fact, that I could only ever appear on a telethon, raising money for damaged people: 'The phone lines are open. Pledge us money and we will make him stop.'"
Williams recently said that he is often mistaken for U2 frontman Bono.
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