President Obama slipped up when he signed the guest book at in London, missing today's date by nearly 3 years.
The president mistakenly wrote the date as 24 May 2008.
Above the date, Mr. Obama and First Lady Michelle Obama wrote, It is a great privilege to commemorate our common heritage, and common sacrifice.
A Westminster Abbey spokesperson confirmed it was indeed Mr. Obama who wrote the wrong date, the Telegraph reports.
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