Philip, who is 96 and also holds the title Duke of Edinburgh, has spent the ensuing decades supporting his wife in her role as head of state. At their 50th wedding anniversary, Elizabeth praised her husband as "quite simply... my strength and stay all these years."

The royal family is reportedly holding a gathering at Windsor Castle to celebrate Monday's anniversary. The royal couple has four children, eight grandchildren and five great-grandchildren.

Buckingham Palace marked the occasion by releasing several new portraits of the couple, taken in the White Drawing Room at Windsor Castle by photographer Matt Holyoak.

The Royal Mail has issued a series of commemorative stamps. And at Westminster Abbey, bell-ringers sounded a full celebratory peal - lasting more than three hours - in tribute.