Pop star Lily Allen has had her US working visa revoked after being stopped at Los Angeles airport.

The singer was detained for five hours and questioned over her arrest in March for an alleged assault on a photographer in London.

She had flown into the US from Australia to attend tonight's MTV video music awards launch in Las Vegas.

Her spokesman said of the incident on Sunday: "Lily was questioned and her work visa was revoked. She was detained for five hours but not strip searched. Understandably she was upset by it."

The 22-year-old is due to return to the UK in the next few days but needs a US work visa to begin a tour there in September.

Allen told the Daily Mirror newspaper: "I am trying everything I can to sort this out.

"It is my intention to play my American dates in September. This depends on the authorities granting me a new work visa.

"I want my fans to know that I will do everything I can to be back in America in September. I don't like letting my fans down and this is a situation that I am sure we can sort."

Allen made headlines in June when she was arrested after a photographer alleged she assaulted him near the Wardour Club in London’s Soho in March.

Last week the singer was forced to deny a further assault after an Australian photographer alleged she attacked him at Melbourne airport.

Allen, the daughter of actor Keith Allen, found fame last year after her debut single Smile went to number one on the UK music charts.

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