Movie bosses have been criticised for hiring the American film legend to play the U.K.'s first female prime minister in The Iron Lady, but Broadbent, who will play Thatcher's husband Denis, believes she is the best choice for the role.
And he's convinced Streep actually has an advantage over a British star because she will bring an "outsider's view" to her performance.
He tells NYMag.com, "I think years ago a film about Thatcher was attempted, and they had a phone-in vote on a BBC morning news programme (in Britain): 'Who do you think should play Margaret Thatcher?' And Meryl actually came out on top!
"I think it's perceived that Thatcher needs a star, really, and she's perfect casting in many ways. She's got a good look, and she'll absolutely do it in a brilliant way. She's also got an interesting eye on the script: She can bring an outsider's view on the story, so that it won't become a lazy, parochial piece that Brits understand but where nobody else really knows what's going on. She can ask the questions that foreign audiences will ask."