Prince Charles will make his youngest brother Edward the Duke of Edinburgh, but not for another eight years.
Dickie Arbiter, a former press officer for Buckingham Palace, has addressed reports that Charles would block his brother taking the title previously held by their father Prince Philip, who died in April.
The title fell to Charles as the oldest son. Edward, the Earl of Wessex, has been waiting for 20 years to inherit the title, which is reportedly what his father wanted.
But there has been speculation Charles would withhold the Dukedom in a bid to slim down the title-heavy monarchy.
However, Mr Arbiter claims the Prince of Wales is simply waiting and has no plans to defy his late father’s wishes, according to The Sun.
He said: “That Prince Edward will become The Duke of Edinburgh in the next reign was his father’s and is his mother’s wishes and Prince Charles won’t go against those.
“It won’t happen immediately, but by 2029, when Edward turns 65, it will.”
He added: “Time for speculation, without substance, to cease.”
The title has long been expected to be passed to Edward and in 1999 Buckingham Palace announced he would succeed his father in “due course”.
Edward and his family have become increasingly important to the monarchy after Prince Philip’s death.
His wife Sophie was called the Queen’s “rock” after she became a widow, and one courtier claimed: “If you’re asking who is Her Majesty’s favourite child, it’s none of them, it’s her daughter-in-law.”
Both also gave moving statements to the press after Philip died, and have since carried out a range of royal duties to support the monarch.
Last month Edward told the Daily Telegraph: “It’s a very bittersweet role to take on because the only way the title can come to me is after both my parents have actually passed away.
“It has to go back to the Crown first. My father was very keen that the title should continue, but he didn’t quite move quickly enough with Andrew, so it was us who he eventually had the conversation with.
“It was a lovely idea; a lovely thought.”
In a separate interview, Edward told the BBC: “It was fine in theory, ages ago when it was sort of a pipe dream of my father’s . . . and of course it will depend on whether or not the Prince of Wales, when he becomes king, whether he’ll do that, so we’ll wait and see.”
The Prince of Wales says reports about the title are “speculation”. He can only make that kind of decision when he is King.
A spokesperson for Charles told People: “All stories of this nature are speculation and no final decisions have been taken.
“It would be inappropriate and disrespectful to the Queen to comment on matters of accession and we will be maintaining our long-standing policy of not doing so.”
Buckingham Palace also declined to comment.