In an interview with Angeleno the Black Swan star says the singer made her cry with laughter while they filmed the romantic comedy No Strings Attached.
'Justin and I play best friends who decide to be friends with benefits,' the 27-year-old told the US magazine. 'There wasn't one day on set when I wasn't on the floor, crying-laughing.
'Justin always thought it was funny that I would be on the phone with my parents, speaking Russian and randomly breaking out into English.
The Ukraine-born star's comments come just one week after a source reportedly told People magazine that they are 'friends' after the two were seen socialising at the Screen Actors Guild Awards.