A spokesman for the former Duke of York told The Daily Telegraph that Fergie had plans to be out of the country on the big day even though her two daughters will be in attendance.
The newspaper said Saturday that the duchess had made other plans despite earlier media reports that William had wanted her on the guest list.
"She never expected to be invited or to attend," the spokesman said. "She will be overseas at the time."
Ferguson's daughters, Beatrice and Eugenie, are clos with both William and Kate and will be on the guest list, the Telegraph said.
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