The music industry veteran told the show's official site that he got an eyeful of the Sight Of You singer when he walked into her dressing room.
"Ha. Walking in on Tulisa with no clothes on. I sauntered into her dressing room and she was totally naked," he said.
"That gave me quite a shock! She looks great though, it has to be said."
And the 60-year-old, who today settled a libel case with The Sun newspaper, also claimed that Tulisa was "in love" with her new boyfriend - footballer Danny Simpson.
"I can tell - she looks really happy and is letting me get away with murder on the show! I enjoy winding her up by calling her a WAG."
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