BEIJING, Aug. 4 (Xinhuanet) -- Republican John McCain claims his recent campaign ad mocking Democrat Barack Obama with images of Paris Hilton and Britney Spears was an attempt to add humor to the U.S. presidential race, but Paris' mom isn't laughing.

    On Sunday, Hilton's mother, Kathy Hilton, voiced her disapproval. Kathy Hilton and her husband donated a total of 4,600 U.S. dollars to McCain's campaign earlier this year.

    "It is a complete waste of the country's time and attention at the very moment when millions of people are losing their homes and their jobs," Kathy Hilton said in a short article posted on the liberal Huffington Post website. "And it is a completely frivolous way to choose the next president of the United States."

    The ad plays on Obama's popularity by dissing him as a mere celebrity, like Hilton and Spears. The Obama campaign has said the ad is proof that McCain would rather launch negative attacks than debate important issues.

    McCain on Friday denied that his campaign had taken a negative turn, saying, "We think it's got a lot of humor in it, we're having fun and enjoying it."

    Kathy Hilton, however, was unpersuaded, calling the ad "a complete waste of the money John McCain's contributors have donated to his campaign."

    (Agencies)