King Charles will reportedly make Prince Edward the Duke of Edinburgh following a "change of heart".
The King was previously rumoured to have been considering passing over Prince Edward in favour of Princess Charlotte, the seven-year-old middle child of Prince William and Kate Middleton, which she would take up once she was old enough.
His youngest brother considered the decision to be a "slap in the face".
The change of heart is said to be part of the new King's effort to make amends with his youngest brother.
King Charles changed his mind after initially favouring giving the title to Princess Charlotte,
A source close to Edward told the Daily Mail: "It was a slap in the face, particularly when Edward has been such a help to Charles over the Andrew farrago.
"Also because the Queen had promised him the title before she died and it was always believed by Edward and Sophie that, in time, the title would then be passed down to their son, Viscount Severn.
"Now it does look like the tide is turning. Clearly the King has had time to reflect on the late Queen's wishes."
The title of the Duke of Edinburgh has historically been important to the maintenance of the union with Scotland, at present facing mounting challenges.
It is also possible that Charles will request that title revert to the Crown from Edward instead of passing on to his heirs.
A Buckingham Palace spokesperson declined to comment.
