Britain's Prince Harry salutes, during a ceremony ahead of Armistice Day, at the Fields of Remembrance, Westminster Abbey, in London. Photo / AP
Prince Harry has been accused of breaking military rules by wearing a beard while on official duty in a British Army uniform.
The 33-year-old left the military in 2015 but appeared at the Cenotaph in London for the Remembrance Sunday service with a full beard.
Despite no longer being a member of the armed forces, a serving military member in the elite cavalry regiment was unhappy that Prince Harry had not shaved for the occasion, according to the Daily Mail.
They said: "Prince Harry is letting us all down. There's no place for beards in the Queen's cavalry. He should have shaved it off for such an important day."
A spokesman for the Ministry of Defence told MailOnline: "On background I can confirm that Prince Harry is no longer a serving officer and therefore does not have to comply with any of these regulations.
"He is, however, a member of the Royal Family and at times his duties require him to don the uniform of a tied or associated regiment and does so with a beard, as did his great-great-grandfather before him."
Prince William and Prince Andrew both appeared at the Remembrance Sunday service cleanshaven, yet Prince Harry had a beard when paying his respects at the Cenotaph service in London.
The British Army rules does not allow beards, except in a few rare circumstances, such as when a soldier is suffering from a skin complaint, or has strong religious reasons for retaining facial hair.
Sikhs are not allowed to cut their own hair, and can thus retain their beards while in uniform, for example.
Special Forces or others on covert operations are also permitted to grow beards when behind enemy lines, but they would not wear them on parade.
There is also a tradition that allows a very small number of Pioneer Sergeants to wear a beard when on official duty, but members of the Queen's personal guard have never been allowed to do so.
The Queen, Harry's grandmother, is Colonel-in-Chief of the Blues and Royals, while the Colonel of the Regiment is Princess Anne, his aunt.
It is one of the two cavalry regiments of the Household Cavalry - the other is the Life Guards - and can trace its history back to Oliver Cromwell's New Model Army of the 17th Century.
Throughout the centuries, officers have been known for their clean-cut appearances, although some occasionally grew moustaches and connected side-whiskers, especially when serving in Muslim countries.
The Royal Navy - in which Harry's father, Prince Charles, served - has always been allowed beards, but officers are told to shave them off it they are not full enough.
Prince Harry left the Army in 2015, aged 31, after being commissioned as a Cornet, the equivalent of Second Lieutenant in the Blues and Royals, which after the Life Guards is the second most senior regiment in Britain.
Harry now concentrates on charity work and other Royal duties, but would normally be expected to abide by military regulations when in uniform.