Prince Andrew is faced with another major "letdown" as King Charles prepares for his coronation.

The Duke of York is said to be "furious" over the possibility that he’ll be banned from wearing his ceremonial roles when the king is crowned on May 6. The 63-year-old, a knight in the Order of the Garter, was expecting to wear his grand regalia, the Mirror recently reported. However, the king is allegedly "torn" over this decision.

"The letdown for Charles' younger brother may be even worse than what has been reported," Christopher Andersen, author of "The King," told Fox News Digital. "Prince Andrew would normally have been entitled to wear something even grander than his blue velvet Knight of the Garter getup."

King Charles and Prince Andrew wearing royal regalia

According to reports, Prince Andrew (right) may be banned from wearing his ceremonial robes at King Charles' coronation. (Leon Neal/AFP via Getty Images)

"As the king's brother and the Duke of York, he would presumably wear the same jaw-dropping costume Prince Philip wore at Queen Elizabeth's coronation: a flowing red velvet robe draped with five ermine tails, not to mention his own coronet," Andersen shared. "This may be just one more example of the palace's desire to make this an ‘animal cruelty-free' coronation, and that means no ermine - which, by the way, has been a staple of the royal coronation wardrobe for centuries."

"Maybe nobody in this coronation ceremony will be wearing ermine - or fur of any kind, for that matter," Andersen continued. "[But] being a Knight of the Garter is a big deal - it is the senior order of knighthood in the realm - but not as big as being a duke and the brother of the king."

According to the outlet, the king's coronation will be a "Collar Day," which means members of the Order of the Garter can wear the collar that signifies the British orders of knighthood that they belong to.

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Prince Andrew, Duke of York attends the Order of the Garter Service at St George's Chapel

Prince Andrew, Duke of York attends the Order of the Garter Service at St. George's Chapel on June 17, 2019, in Windsor, England. The royal is said to be ‘furious’ that he possibly won't get to wear the traditional regalia at his brother's coronation in May. (Mark Cuthbert/UK Press via Getty Images)

The Order of the Garter is known as the oldest order of chivalry in the world. It is nearly 700 years old.

The outlet noted that Andrew may be ordered to wear "a lounge suit" after he was stripped of his military appointment as Colonel of the Grenadier Guards. He remains a vice admiral because of his service in the Royal Navy.

"If the king doesn't allow his own brother to at least wear his Knight of the Garter robes - or barring that, the ceremonial uniform he is still entitled to wear as a vice admiral in the Royal Navy - it will be humiliating for Andrew," Andersen explained. "Conversely, at this historic moment, does the new king want to strike yet another note of disharmony in the royal family? It was unsettling enough to watch Prince Harry scowling as he was initially forced to wear a simple suit at Queen Elizabeth's funeral. King Charles clearly does not want a repeat of that."

Prince Andrew wearing a suit during Queen Elizabeth's funeral

Prince Andrew wasn't allowed to wear his military uniform during Queen Elizabeth II's funeral in September. (Photo by Christopher Furlong/Getty Images)

Royals expert Hilary Fordwich alleged to Fox News Digital that Charles, as well as Prince William, prefer to keep the disgraced Duke of York "away from public engagements in general," including the coronation. This, she claimed, is the root of Andrew’s fury.

"This has resulted in him being purportedly ‘furious’ at not being able to play a part," Fordwich explained. "He believes it is he who is being disrespected and being dictated over something he is fully entitled to wear."

"Given that the coronation will be a ‘Collar Day’ for the Order of the Garter, an elite club of just 24 members, they will be wearing collars depicting their knighthoods," she explained. "But Prince Andrew, albeit still a Knight of the Garter, is projected to be only permitted to wear a lounge suit. He already was not allowed to wear his military uniform at Queen Elizabeth’s funeral. He previously held eight military titles in total but . . . he was unceremoniously stripped of his royal patronages and military titles by his mother."

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A black and white photo of Queen Elizabeth's coronation in 1953

Prince Philip, the Duke of Edinburgh, is seen here paying homage to Queen Elizabeth II during her coronation in 1953. (Fox Photos/Getty Images)

"He lost, for example, his military appointment of Colonel of the Grenadier Guards – the bearskin-wearing senior infantry regiment – but remains a Vice Admiral, the uniform he has wished to wear at previous formal occasions such as his mother’s funeral but was flatly denied," Fordwich added.

Previously, it was reported that Andrew was "resisting" the king’s wishes for him to leave the Royal Lodge for Frogmore Cottage, the former UK home of the Duke and Duchess of Sussex.

According to royal experts, there's a reason why Charles, 74, eyed his younger sibling for the move. Andrew’s annual allowance of nearly $300,000 is being cut in April, The Telegraph reported. Friends claimed to the outlet that this will make it difficult for the duke to maintain the 98-acre Windsor property. Andrew's main source of income is his Royal Navy pension and a "substantial inheritance" from his late parents.

King Charles in green suit adorned with medals and chains sits in a royal chair next to a crown

King Charles and his wife Camilla will be crowned on May 6 at London's Westminster Abbey. (Alastair Grant)

A source told The Sun that Andrew is "resolute" that he will stay at Royal Lodge. According to the outlet, he hasn’t accepted the offer to move yet.

Andrew stepped back from royal duties in 2019 amid his controversial connection to the late American financier and convicted sex offender Jeffrey Epstein. He was also stripped of his honorary military titles. Before her death in 2022, the queen also removed his honorary leadership of various charities, known as royal patronages, and barred him from using the title "His Royal Highness" in official settings.

The council in the northern city of York voted unanimously to withdraw the prince’s "freedom of the city." The honor was awarded to Andrew in 1987 after the queen made him the Duke of York. He is the first person to be stripped of the status, an honor that dates back to medieval times. Local leaders have since argued that Andrew should also lose the title of Duke of York. A spokesperson for Andrew declined to comment at the time.

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Prince Andrew looking away from the camera

Prince Andrew stepped back from royal duties in 2019. ( REUTERS/Neil Hall)

In 2022, a U.S. judge dismissed the sex abuse lawsuit against Andrew, who reached a settlement with accuser Virginia Roberts Giuffre. The prince made a substantial donation to his accuser’s charity and declared that he had never meant to malign her character.

Andrew strenuously denied Giuffre’s allegations after she sued him, accusing the British royal of sexually abusing her while she traveled with Epstein in 2001 when she was 17.

Giuffre, 39, reached the settlement with Andrew after the judge rejected the prince’s bid to win early dismissal of the lawsuit.

The Associated Press contributed to this report.