The brothers are wearing the dress uniform of the Household Cavalry as worn for The Queen's Birthday Parade in 2008
The first double portrait of Princes William and Harry has gone on display at The National Portrait Gallery.
Prince William and Prince Harry: a new portrait by Nicky Phillips shows the royal brothers in Clarence House engaged in conversation.
The brothers have been depicted together in works of art before but always with other individuals.
Phillips said they were "good company" and she hoped that she had captured their "brotherly banter."
Sandy Nairne, Director of the National Portrait ,said: "The first portrait of the Princes captures them formally dressed, but informally posed. It is a delightful image which extends the tradition of royal portraiture."
William, 27, and Harry, 25, are wearing the dress uniform of the Household Cavalry as worn for The Queen's Birthday Parade in 2008.
The sittings, which took places mainly at Phillips' studio, were arranged around the Princes' Army careers and official engagements.
The artwork is displayed as part of the National Portrait Gallery's Contemporary Galleries.
Other portraits of the royal family feature, including Conversation at the Royal Lodge, Windsor, painted by Sir James Gunn in 1950 and Alison Watt's portrait of the Queen Mother, commissioned by the Gallery in 1989.