Emily Blunt in tears over Edge of Tomorrow body armour

British actress Emily Blunt sobbed in front of Edge Of Tomorrow co-star Tom Cruise when she first tried on the heavy armour she would have to wear for the duration of the shoot - because it was so heavy.

The prospect of acting in the 85 pound (38.5 kilogram) suit for five months was a little too much for The Devil Wears Prada star and when Cruise asked her how she felt, she broke down.

She explains, "The first time I put it on I cried. I remember Tom was there... to see how the exosuit fitting went... and I'm not really a crier, but I felt completely overwhelmed that I was gonna have five months of this. We put it on and he said, 'How are you doing...? You OK?'"

Blunt burst into tears and said, "I wasn't really expecting it to be this heavy."

But she adds Cruise managed the situation well, telling his co-star, "Come on, stop being such a wuss!"

The actress, who also mastered Krav Maga and took gymnastics and sprint training classes to perfect her look for the sci-fi movie, insists she was OK after the brief meltdown.