Spencer Pratt has refueled the long-standing feud between him and Lauren Conrad.

On Tuesday's episode of The Tyra Banks Show, he says that he is "100%" sure there was a rumored sex tape starring Conrad.

"I know for 100% fact it did exist – 100%!" he declares.

Banks asks if Pratt had actually seen it.

"I would never watch that!" Pratt says. "I would rather throw up... but I know for a fact, and I would take a lie detector test."

Heidi Montag — who appeared alongside Pratt on the show — also claims the tape was "not a rumor. From what I have heard from confirmed sources... her ex-boyfriend was going around trying to sell it."

Banks then asks Montag, if she hadn't seen the tape, how could she be so sure it existed.

"Well, I mean, I am not sure she has it anymore... but from what I've heard..."

Montag adds, "I am not really allowed to elaborate."

In April 2007, Conrad told Usmagazine.com, "There is no sex tape that exists."

Conrad and Montag's friendship fizzled after she accused her of spreading rumors about the raunchy tape.

Tell Us: Do you believe Spencer?

source: http://www.usmagazine.com/spencer-pratt-100-fact-lauren-conrad-sex-tape-...