The British actor had to be coached on his British accent, co-star Christina Ricci revealed in an interview on "Jimmy Kimmel Live", Us Weekly reported.
Ricci, 34, and the Twilight hunk star in Bel Ami, a film about a young man who rises to power in Paris by manipulating wealthy women.
Ricci had to speak in an English accent and she said Pattinson, 26, made fun of her sometimes.
"They hired a wonderful accent coach who coached me ... and also coached him because he spent a lot of time in LA," she explained.
"I got to make fun of him because he's actually British and sometimes would sound like he was a Valley girl. And he made fun of me because I was trying to be British and would sometimes sound like a Valley girl.
"But really I was the problem. Sometimes we would do scenes and I'd turn to him and I would [ask], 'Did that sound OK?' And he'd [say], 'No.'"
Recently Pattinson praised his girlfriend Kristen Stewart for her English accent in Snow White and the Huntsman.
"She's really good at it," he told MTV News. "She's really good."
Robert Pattinson had to be coached on British accent, says co-star
