A St James's Palace spokesman would not comment on whether William had been informed about the issue or if they were considering any form of legal action against the magazine.
The publication comes less than six months after the magazine produced a 26-page spread showing Kate topless during a holiday in France.
At the time Chi's editor Alfonso Signorini defended his decision to publish the pictures saying: "I am a director of a newspaper not a supermarket, I don't sell artichokes and carrots, I sell photographic scoops."
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