Despite recent tabloid reports that Pitt was cozying up to Sienna Miller at last weekend's Glastonbury music festival in the U.K., and that he was also spotted getting flirty with supermodel Elle Macpherson -- who recently split from billionaire Jeffrey Soffer -- in Los Angeles, a source says the actor isn't dating anyone. The source adds that Pitt is actually friends with a male pal of Miller, and that there have been no romantic displays between him and the British actress. Interestingly enough, in an interview with Miller in April about Pitt, when he made a surprise appearance at The Lost City of Z premiere in Los Angeles, Miller stated, "He's involved in the film in that he found the book and developed it and hired James [Gray, the director]. And I think as a producer was very active."