SHE rode in an open-topped Ascot landau carriage, decorated in her racing colours with garlands of gold and blue flowers, and pulled by four grey horses.

A 41-gun royal salute was fired from Green Park, earlier than expected, as the horse-drawn carriage entered the Buckingham Palace forecourt.

Her short ride from her Clarence House residence saw her cheered every inch of the way, with an estimated 40,000 people packing The Mall to share the Queen Mother's 100th birthday celebrations.

As she stepped out on to the balcony, the band of the Coldstream Guards, in the Palace forecourt below, played Happy Birthday To You and one of the Queen Mother's favourite pop songs, Congratulations.

The Queen Mother moved her hands and arms to the rhythm of the music as the band struck up the Cliff Richard hit.

She then took the nation's salute, as she was joined by the rest of her family, every Royal wave met by a loud cheer.

All senior Royals celebrated with the Queen Mother at a private family lunch amid the splendour of the Palace's Bow Room. Palace staff were each given a celebratory glass of champagne.

The public celebrations began at 11.45am, when the Queen Mother, who wore her favourite shade of light blue, walked slowly, with two sticks, to the gates of Clarence House.

Close by was the attentive Prince of Wales, sporting a blue cornflower in the lapel of his double-breasted grey suit.

Then came the first public tribute of the day as the King's Troop Royal Horse Artillery rode past, followed by the band of the Irish Guards, playing Happy Birthday, with Grena-dier Guards marching behind.

Standing in the centre of the open gates, the Queen Mother smiled broadly and waved.

The Queen's postman arrived in a bright red, electric-powered Royal Mail van with a special delivery. Struggling to open the envelope, the Queen Mother turned to her equerry, Captain de Rouet, and asked: ''Can you use your sword?''

To the amusement of the Prince of Wales, the Irish Guards officer drew his sabre and slit it open.

Inside was a new-look 100th birthday card, which has replaced the royal telegrams.

The handwritten message inside the card from her daughter read: "On your 100th Birthday all the family join with me in sending you our loving best wishes for this special day. Lilibet.''