Britney started her Circus tour in March
Britney Spears is "extremely upset" over reports fans walked out during her first Australian tour because she was lip-synching, her promoter has said.
Paul Dainty told The Australian newspaper the claims were "an absolute fabrication".
Australian media suggested some fans left after three songs due to Spears's miming and "lacklustre" performance at Perth's Burswood Dome.
A spokesman for the venue said it had received no complaints about the show.
"It's the biggest lie I've ever heard," Mr Dainty said.
"I'm so angry. We can take heat if there's something wrong and people can review shows badly - that's something you have to live with - but to say people stormed out of the show was an absolute fabrication.
"Britney is aware of all this and she's extremely upset by it - she's a human being," he added.
The singer has been at the centre of debate over lip-synching since she arrived in Australia last week, even though it is no secret she mimes during her show.
Virginia Judge, the fair trade minister for the state of New South Wales, ignited the argument by suggesting concert tickets should carry disclaimers about whether parts of concerts were pre-recorded and mimed.
Mr Dainty said it was well known parts of Spears's concert was lip-synched and denied the suggestion it was hidden.
"It's been all over the internet for nine months - this show is about an incredible spectacle, which it is," he said.
More than 17,000 fans, who had paid between AUS$200-$1500 (£110-£830) for a ticket, attended the first date on Spears's tour.
The singer is performing 15 dates across the country as part of her Circus tour which kicked off in New Orleans in March.