Hilton 'at war' with Mischa Barton

Paris Hilton has reportedly fallen out with Mischa Barton backstage on Good Charlotte's UK tour.

The US socialite, who is currently dating guitarist Benji Madden, is apparently upset that Barton keeps turning up to their gigs.

Barton is going out with Taylor Rocke from LA retro rockers Rooney, who are supporting Good Charlotte during their British jaunt.

According to The Mirror, both female stars have clashed and are in a "full-on war".

Hilton revealed last week that she was the happiest she had ever been in her life thanks to her new relationship.