Former New York Mayor Rudy Giuliani said only "stupid" people believe that the White House is not covering up the origins of a small amount of cocaine found last weekend.

"Biden never tells the truth. It's almost useful when they say something when somebody like that little lying press secretary that he has, the one who's now given us three different places [for] the cocaine," he said on Sunday. "I mean, they're a mouthpiece — they're a mouthpiece for the crooked White House. How can you possibly say the day after that you just found out about the crime that's not — you're not going to solve it...Can you imagine if there's a murder this morning, and the acting police commissioner shows up and says let me think about this? This may never be solved."

Giuliani said anyone who believed the White House explanation was "too stupid" to listen to his show.

"It this is a damn lie, and it tells you right away there's a cover-up," he insisted. "You gotta be — I'm going to tell you this. If you don't realize this is a cover-up, you're too stupid to listen to this show. Go listen to some other show. Go listen to CNN or MSNBC and make yourself happy, but you obviously don't have a critical intellect."