The Duke of York has paid tribute to the Queen, saying: "Mummy, your love for a son, your compassion, your care, your confidence I will treasure forever."
Prince Andrew, who is no longer a working royal, accompanied his statement with a black and white image of his mother holding him as a baby in March 1960.
He ended it with the words God Save The King in honour of his brother Charles.
The Duke of York said he would miss the late monarch's "insights, advice and humour", saying he "found your knowledge and wisdom infinite".
The statement read: "Dear Mummy, Mother, Your Majesty, three in one. Your Majesty, it has been an honour and privilege to serve you.
"Mother - of the nation, your devotion and personal service to our nation is unique and singular; your people show their love and respect in so many different ways and I know you are looking on honouring their respect.
"Mummy, your love for a son, your compassion, your care, your confidence I will treasure forever. I have found your knowledge and wisdom infinite, with no boundary or containment.
"I will miss your insights, advice and humour. As our book of experiences closes, another opens, and I will forever hold you close to my heart with my deepest love and gratitude, and I will tread gladly into the next with you as my guide.
"God save The King."
Prince Andrew stepped down from public life over his friendship with paedophile billionaire Jeffrey Epstein in 2019.
He has been stripped of his honorary military roles, including Colonel of the Grenadier Guards, and has given up his HRH style.
At one point during the commemorations for the Queen's death, he was heckled by a man in the crowd.
The Duke of York has settled a civil sexual assault case to a woman he claimed never to have met. The exact amount of the settlement has not been disclosed, but some reports at the time put it at £12m.
Virginia Giuffre sued him for allegedly sexually assaulting her when she was 17 after she was trafficked by Epstein.
Andrew has always denied the claims.