At a "Love and Other Drugs" press conference in New York Saturday, Hathaway jokingly bristled when her hunky co-star, 29, was asked about Swift, 20.
"Hang on, hang on. I have to say something. I have been Jake's on screen love interest for years," Hathaway, 27, interjected. (She and Gyllenhaal were first paired together in 2005's "Brokeback Mountain.") "You keep the conversation to me and only me or otherwise I'm going to get nasty! Thank you."
Gyllenhaal quipped: "Don't get Ella Enchanted pissed off."
"Don't get Ella Enchanted pissed off, and I'm not obedient," the actress added.
Gyllenhaal did speak about their new film's theme and the quest to find true love. "The stakes are always high in love," he said. "It happened premature for these [characters], but when you do love someone you have to think about those things early and hope for the best, whatever that is."
Gyllenhaal, who split from Reese Witherspoon late last year, spent two weekends in a row with Swift. The duo palled around in the NYC area (brunching in Brooklyn, apple-picking upstate) Oct. 23 and 24th, and hit California (for some poolside time and an ice cream date) over the Halloween weekend.
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