LONDON (AP) -- Britain's Royal Mail is celebrating Prince William and Kate Middleton's wedding with a new set of stamps that feature their official engagement portraits.
Two pictures of the couple taken by fashion and celebrity photographer Mario Testino will be printed on the set of commemorative stamps.
The collectibles have been approved by William and will be released on April 21, the birthday of Queen Elizabeth II.
William has been featured on stamps twice before -- to mark the Queen Mother's 100th birthday on August 4, 2000, and three years later to mark his 21st birthday.
The stamps can be ordered from Royal Mail's website from April 7.
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