Duke of Edinburgh becomes Lord High Admiral of the Navy
23 November 2011 Last updated at 17:43 GMT
The Queen has formally presented the Duke of Edinburgh with the title and office of Lord High Admiral of the Navy to mark his 90th birthday.
Prince Philip gave up a promising naval career for royal duty - some see the Queen's birthday gift as an acknowledgement of his sacrifice.
The Duke laughed as a senior naval officer explained that a previous holder of the title, the Duke of Clarence, later William IV, was asked to resign.
The Queen and Duke were also shown a display of precision drumming by the Royal Marines Corps of Drummers.