John Mayer has defended Britney Spears for lip-synching in Australia.

The “Gravity” singer - who is also in Australia promoting his latest album - blasted fans who had called for a refund after the “Womanizer” star’s show in Perth after she sparked outrage by not singing live for her whole performance.

“If you’re shocked that Britney was lip-synching at her concert and want your money back, life may continue to be hard for you,” Mayer wrote on Twitter.

Britney, 27, was said to have hid in her hotel room on Saturday following her performance on Friday night. “Britney is aware of all this and she’s extremely upset by it,” a rep for the star said.

In response to the show, fans protested about the high ticket prices and “impersonal” nature of the concert. Concertgoer Wendy Di Renzo, 36, said: “It was so impersonal. She did not interact with her audience. There were no big TV screens projecting the action, so if you didn’t know Britney, you might have even doubted it was her.”

Complaints against the “Gimme More” singer also included that she never referred to Perth by name, instead giving a generic welcome to fans, saying: “What’s up Australia?.”

“I want my money back or I want her to sing properly. The ticket cost me $200 and she lip-synched the whole thing,” another fan, who left the show early, stated.

Politicians in three Australian states - Western Australia, Victoria and New South Wales - have now called for new laws to force music promoters to disclose whether a concert will be live or lip-synched beforehand.

Britney will next perform in Melbourne on November 11.

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