The 66-year-old actress was awarded Best Actress Oscar in 2006 for her role as the monarch in the film, reported Contactmusic.
"She's an icon all over the world. Everybody knows what she looks and sounds like. I knew I had to get those things right, but I wanted to go beyond a simple impersonation. So yes, I was very, very nervous," she said.
Mirren has also starred in films like "Calendar Girls", "Gosford Park" and "The Madness of King George".
