Emily Blunt ''laughed hysterically'' when she met Barack Obama.
The 29-year-old 'Salmon Fishing in the Yemen' star was attending the Kennedy Center honours at the White House with husband John Krasinski when she got an unexpected invitation to meet the American President.
But her emotions soon got the better of her and her awe turned in to uncontrollable giggles.
Recalling the embarrassing December meeting, she said: ''I was so starstruck ... we were at the White House having cocktails and this woman said, 'Would you like to meet President Obama?'
''They introduced me and then he turned to me and went, 'Oh. Oh. You are a wonderful actress'.
''And I laughed, screechingly and hysterically, I couldn't stop. They had to usher me away. I fell apart. I don't know what happened to me. He looked nine-feet tall. I think my eyes rolled back in my head.
''I gave [First Lady] Michelle a hug and she had skin like silk.''
Whilst filming new movie 'Your Sister's Sister' alongside Rosemarie DeWitt, Emily reveals one crying scene was made possible by a joke about her private parts.
In an interview with Elle magazine, she explained: ''I remember one scene when the director Lynn Shelton came up to Rosemarie and whispered in her ear: 'Say something that would really embarrass Emily'.
''So Rose told this story that involves my nether regions ... Basically, her friend was going out with this boy and he'd said to her, 'I think you need to shave your pubic hair because it's really pouffey in your underwear', and so we're doing this scene and Rosemarie just goes: 'Do you remember when Chris told you to shave your bush?'
''I went completely crimson, I was so mortified. For the first time ever on film, I cried with laughter and they caught it, they captured that golden moment when it was completely genuine.''