Britney Spears' lip-synced shows are causing controversy in Australia - one of the country's leading politicians is urging ticket agencies to warn fans when artists plan to mime.

Spears is currently performing Down Under as part of her Circus world tour, but critics have slammed the star for failing to sing live during the shows.

Now the New South Wales Minister for Fair Trading, Virginia Judge, has waded into the debate - insisting ticket agencies should publish a disclaimer to stop gig-goers feeling cheated when an artist fails to provide any live vocals.

Judge has branded Spears' shows a "Mickey Mouse performance", adding: "Let's be clear - live means live. If you are spending up to $200, I think you deserve better than a film clip. The NSW Government would be happy to look at options, such as a disclaimer on a ticket which would warn consumers a performance is pre-recorded."