Miley Cyrus and Liam Hemsworth have had an on-off relationship since 2009

We thought The Hunger Games' jabberjays, tracker jackers and careers were vicious.

But as the film's star Jennifer Lawrence battles CGI creatures on screen, she's caught up in a real-life war with a green-eyed monster: Miley Cyrus, girlfriend of her hunky co-star Liam Hemsworth.

In the hit film, Liam, 22, plays Gale Hawthorne, one of the love interests of Jen's character Katniss Everdeen.

But while he and Jen, 21, work the publicity circuit, behind the scenes, things are decidedly frosty between Jen and Miley.

'It started when Miley tried to give Jen advice about handling fame,' says our source.

'It was a bit of an insult as Jen's been working since she was 15 - and has already been nominated for an Oscar for Winter's Bone.'

'So Miley got the shock of her life when Jen told her to mind her own business.'

'Now it's pretty much all-out war.'

With relations already strained, Miley, 19, blew her top after Liam, whom she's been dating for three years, started raving about what fun it was on set.

Read more about Miley Cyrus and Liam Hemsworth in Now magazine dated 9 April 2012 - out now!

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