Walliams and Alesha Dixon and have joined Cowell and Amanda Holden on this year's Got Talent panel, and the Little Britain star described the ITV1 show as "the best fun you can have".
"I can't believe they pay me to do it. You can't prepare for it. You just have to sit there and react to whatever is on. It's so much fun and I love working with Simon… he's a very naughty man," said Walliams.
Teasing his new boss, the comic said: "[Simon] really is hilarious. I've never had a job where so many people and friends in the business have asked me questions. 'What's he like? What's he like? Is he gay?'"
David Walliams won the 'Landmark' award at the National Television Awards last night (January 25) for his Sports Relief charity swim up the Thames.
Comparing his charity feat with working on Britain's Got Talent, he joked: "Just like when you attempt to swim the Thames, [when you work with Simon Cowell], you have to cover yourself in lard."
Walliams, Cowell and Dixon are currently touring the UK with Got Talent auditions. Amanda Holden is missing the latest batch of try outs following the birth of her daughter Hollie Rose Hughes.
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