The Happy Days star is currently in the UK for the First News My Way! tour, supported by uDraw.
Speaking during a live Digital Spy Twitter webchat, Winkler was asked if he would consider joining the celebrity lineup for programmes such as Strictly Come Dancing.
"No. At the moment, no," he said. However, he continued: "Now I have learned never to say never, but at the moment, I would never do it."
Having just completed red button commentary for Strictly Come Dancing, Winkler said that he had "so much fun", naming Harry Judd, Jason Donovan and Lulu as his favourites.
Asked by one fan about his current TV viewing, Winkler said that he is a big fan of Simon Cowell's The X Factor USA and described the music mogul as a "genius".
Winkler, who was recently made an honorary OBE, is continuing the First News My Way! tour, which raises awareness of the needs of children with learning challenges in schools across the UK.
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