Gwyneth Paltrow in a Leotard for "Glee"

Gwyneth Paltrow arriving at a Fashion Night Out at Stella McCartney's London Store

Actress Gwyneth Paltrow is seen here arriving at a Fashion Night Out at Stella McCartney's London Store in Mayfair. Gwyneth looked stunning wearing a black leggings and a white shirt with a white jacket and a pair of black heels on.

Beyoncé and Gwyneth watch Jay Z. at Wireless festival

Madonna and "Jealous" Gwyneth Paltrow Had "Falling Out"

A source close to Madonna, 51, and Gwyneth Paltrow, 37, tells Us Weekly the dear pals, BFFs since 1999, are dunzo.

"They don't speak," says the insider. "I can't tell you exactly why they had the falling out, but Gwyneth can be jealous and competitive."

Although Madonna's rep denies the "breakup," the source says things went downhill slowly for the duo after Madonna split from Guy Ritchie in 2008, leaving "Gwyneth and Madonna with less in common." (Paltrow's been wed to U.K.-born singer Chris Martin since 2003.)

And to be sure, both women have a history of bagging their besties: Madge fell out with Sandra Bernhard around 1991; Paltrow cut ties with Winona Ryder in 1998. In fact, Paltrow (who once called the singer "like an older sister") hinted at a new feud in May's British Vogue: "I'm having a situation right now with a friend where I'm feeling pretty angry."