Appearing on the cover of Vogue magazine is one of the highest honors a Hollywood star can achieve but even the iconic glossy fashion magazine is below the high standards of the British royal family, RadarOnline.com has learned.

Kate Middleton had been rumored to be considering appearing on the coveted cover but politely declined earlier this week, despite editor Anna Wintour trying to persuade her through photographer and friend, Mario Testino, who shot the Duke and Duchess of Cambridge's engagement photos last year.

Now E!Online is reporting that the Queen of England herself is vetoing the idea as she doesn't want her granddaughter-in-law posing for the magazine.

Another day, another hat. Kate Middleton and Prince William attended a special church ceremony Sunday morning, part of the celebration of Prince Philip turning 90.

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Philip turned 90 on Friday, and today he and his wife of 54 years, Queen Elizabeth, came together with 750 of their closest friends to celebrate at Windsor Castle.

William and his brother Harry reportedly became quite close to their grandparents after the death of their mother Diana, and they've welcomed Kate right into the family.

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Legendary fashion designer Oscar de la Renta has taken First Lady Michelle Obama to task because of the gown she wore to the state dinner for Chinese President Hu Jintao, RadarOnline.com has learned.

PHOTOS: Michelle Obama’s Smashing Sense Of Fashion

“My understanding,” de la Renta told WWD, “is that the visit was to promote American-Chinese trade — American products in China and Chinese products in America. Why do you wear European clothes?”

Mrs. Obama wore an elegant red-to-black gown designed by Sarah Burton from the late Alexander McQueen’s design house.  McQueen was British as is Burton, and de la Renta thought Mrs. Obama should have only worn a gown that was made in the U.S. of A.

Even though Mrs. O is the first First Lady in 30 years not to have de la Renta design for her, he insisted his criticism wasn't based on that.

PHOTOS: Michelle Obama’s Smashing Sense Of Fashion

"I'm not talking about my clothes, my business," he said. "I'm old, and I don't need it. But there are a lot of young people, very talented people here who do."

Comedienne Joan Rivers revealed she once ditched a joke about First Lady Michelle Obama from her stand-up routine - because she feared she'd be accused of racism.

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Recalling the wisecrack to shock Jock Howard Stern, the comedy legend said: "We used to have Jackie O now we have Blackie O!"

The audio can be heard here on RadarOnline.com.

Rivers wrote the quip about President Barack Obama's wife in reference to her fashionable dress sense and comparing her to former First Lady Jackie Kennedy Onassis.

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Mrs. Obama, who supports many American designers and is famous for stepping out in J.Crew attire, has officially become one of the fab four of the political fashion world —joining Jacqueline Kennedy, French First c and Princess Diana.

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