Playboy Playmate Victoria Silvstedt

Mischa Barton and Victoria Silvstedt had a dramatic bust-up at a lavish Cannes party on Tuesday.The pair arrived at the exclusive bash thrown by jewellers De Grisogono at Hotel du Cap's Eden Roc club together, but tempers soon flared.Mischa, 21, was reportedly unimpressed with Victoria following her around and tried to shake her off, but her attempts did not go unnoticed by the blond Playboy Playmate. Victoria, 32, was overheard yelling: "Where the hell are you going now? Why do you keep walking away from me?"The former 'The O.C.' star angrily responded, saying: "We're not even going in the same direction. We're not going to the same place."The beautiful stars spent the rest of the evening apart mingling with other guests including Naomi Campbell, Eva Mendes, Kid Rock and Beyoncé Knowles. However, things came to a head when Mischa bumped into an angry Victoria as she tried to leave the party at 4am. A source told Britain's Daily Mirror newspaper: "Mischa was fed up of Victoria's whining and was telling her to move on. But Victoria completely lost it. Just as Mischa was leaving she shouted, 'There goes the b***h! There goes the b***h!'"It was highly embarrassing."Despite the embarrassing episode, other revellers had a great time at the party where they were treated to a performance from former Destiny's Child star Kelly Rowland, who wore $2 million of De Grisogono diamonds.