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.

Find the photo below: