Ryan Phillippe Hits on Rihanna, Amanda Seyfried Fling Cools Off

Credit: Jason Merritt/Getty; Joe Scarnici/Getty Images; Jon Kopaloff/FilmMagic

Is their three-month romance over already?

Ryan Phillippe and Amanda Seyfried were spotted having an intense conversation followed by a lingering embrace at the Chateau Marmont in West Hollywood February 7.

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Days later, Phillippe was already on the prowl: He tried to pick up Rihanna, 22, at the Gucci/Roc Nation brunch at L.A.'s Soho House February 12.

"He said something to the effect of, 'What are you doing tonight?' and she signaled 'sleep,'" a witness tells the new Us Weekly. "She was trying to be polite, but she was genuinely not interested. When a couple of her friends came up to join the conversation, he just walked away."

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The actor, 36, had more luck later that night, when he was seen leaving a house party with a pretty brunette. As for his relationship with Seyfried, 25: "It's casual. They'e friends who hang out romantically from time to time and that's it," says a pal. "At one point, there was a chance it would develop into something more serious, but it never did. There's no commitment."