The former equestrian, 75, made her way to the Horse Guards Parade from Buckingham Palace alongside the Prince of Wales, 43, and the Duke of Edinburgh.

This year, the honour of trooping the Colour falls to the Grenadier Guards, the British Army's most senior infantry regiment, which is celebrating its 370th anniversary.

The Princess of Wales looked typically stunning as she took part in the King's official birthday parade in London today.