British royals Prince William and Catherine, Duchess of Cambridge have expressed their sadness following the death of Prince Charles' brother-in-law Mark Shand.

Travel writer Shand, the sibling of Prince William's stepmother Camilla, Duchess of Cornwall, was hospitalised in New York City on Tuesday (22Apr14) after falling and hitting his head on the pavement outside a nightclub.

The 62 year old died from his injuries on Wednesday (23Apr14).

Prince William and his wife heard the sad news as they neared the end of their tour of Australasia, and they passed on their condolences to the Shand family.

The statement from Kensington Palace reads, "The Duke and Duchess of Cambridge were saddened to learn this morning of the tragic death of Mark Shand. Their thoughts are with The Duchess of Cornwall and her family at this time."