Read more: Saoirse Ronan: shooting ‘Hanna’ was ‘bad-ass’- SEE VIDEO & POLL

Saoirse Ronan told the press this week she enjoyed having the opportunity to kick the ass of her 'Hanna' co-star Eric Bana.

But don't think she's a tough girl, she added that in reality she wouldn't hurt a fly.

The 16-year-old Irish actress plays a teenage assassin in which octane new thriller 'Hanna' but the truth is she admits she feels terrible if she accidentally kills even a spider.

Ronan said: "I've never killed an animal. I actually apologize to flies. Well, not flies. I hate flies. But if a spider dies by accident, I'll say sorry to it. I'm not a murderer."

Saoirse didn't have quite so many qualms about roughing up Eric Bana, who has previously played the angry green superhero the 'Hulk.'

Ronan added: "He is big. He's really big. And he's tall. And he's got huge arms, hasn't he? They're huge!

"It was great actually because I could just go for it. I reckon I did hurt him once or twice. And now I can say that I kicked the ass of the Hulk."

Read more: Saoirse Ronan: shooting ‘Hanna’ was ‘bad-ass’- SEE VIDEO & POLL