In a letter from Buckingham Palace, written in connection with the celebration of Elizabeth's 70 years on the throne, the Queen writes the following: 

"It is my wish that when the time comes, Camilla will be called Queen, formally Queen Consort." 

Camilla Parker Bowles, born Shand is the Duchess of Cornwall, a title she received after her marriage to Prince Charles in 2005. Previously, there have been proposals to call Camilla a princess, but she has avoided using titles previously associated with Prince Charles' first wife Lady Diana. 

"Touch"

A spokesman for Prince Charles said the couple were "moved and honored" by the queen's announcement.