Jessica Simpson has been slammed for allegedly snubbing a charity she has worked with for ten years.

The blonde beauty has been a long-term supporter of Operation Smile, which helps children around the world born with facial disfigurements, and has campaigned tirelessly for them. She even went on a trip to Africa last year to highlight the organization.

However, sources at the charity claim she has done nothing since that trip and were furious when she missed a New York benefit night earlier this week.

An insider told the New York Post newspaper: "She's turned her back on them. She got a lot of good publicity from the charity but refused to let pictures of her be in the commemorative book and hasn't done anything with them in a year."

However, Jessica's spokesperson says she missed the event because she was in Germany, where she was honored at the UNESCO Gala to Benefit Children in Need.

The spokesperson added: "It was partly for her work with Operation Smile. Jess was one of four honorees for her philanthropic work. She sang two songs and the event raised about $3 million to build schools all over the world."

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