AceShowbiz -

A duet between Britney Spears and Heidi Montag on a song called "Dramatic" that has been played at Ryan Seacrest's radio show and circulated all over the net apparently is recorded without both artists' knowledge. Reps from Spears and Montag insisted that their clients know nothing about the song and that the stars had never had a recording session together.

Montag's publicist explained, "Heidi has no knowledge of this recording. She did do a demo of this song for possible use on her record, but that recording had a male vocal on it, not Britney Spears." Meanwhile on the other side, a source told Perez Hilton, "Heidi and Spencer got their hands on an old demo recording of Britney's that never made it onto any of her albums."

"They've been working with a lot of producers on Heidi's new album and one of them gave them the track," the source added. "They decided to turn it into a duet instead of having Heidi re-record the song with just her vocals because they knew they'd get more press this way."

Seacrest who is known to be the host of American Idol show, debuted the track on his breakfast show at KISS FM on Monday, March 3, saying that he got an e-mail of it. Seacrest said, "I just opened an email and there was this track and it said, 'Britney Spears and Heidi Montag'." The full track is put on the radio station's website for fans to listen to.

Britney Spears and Heidi Montag's so-called 'duet':