Britain's Queen Elizabeth II (C) waves to the public on the balcony of Buckingham Palace during the Trooping the Colour ceremony to mark Queen Elizabeth II's 92nd birthday in London, Britain on June 9, 2018. (Xinhua/Tim Ireland)

LONDON, June 9 (Xinhua) -- The annual birthday parade of British monarch Queen Elizabeth II took place in central London on Saturday, and saw the latest addition to the royal family in attendance for the first time.

American actress Meghan Markle, who married Prince Harry, sixth in line to the British throne, last month, attended her first birthday parade as the Duchess of Sussex.

The birthday parade is held each year on a Saturday in the first half of June, and involves more than 1,000 soldiers in ceremonial uniforms and several hundred cavalry soldiers on horseback.

The parade is officially known as Trooping the Color, in which a regiment of soldiers from the Queen's personal division of soldiers, the Household Division, is chosen to parade its flags. This year's regiment was the 1st Battalion, Coldstream Guards.

The Trooping the Color ceremony has been used to mark the monarch's birthday for 260 years.

This dates back to the era of George II, who chose to have an official birthday in June because his real birthday was in November and the weather was often not good enough for a parade.

This year's parade marks the 92nd birthday of the current Queen, who has been on the throne since 1952 and is the longest-serving monarch in British history.

The Queen also marks her real birthday of April 21, but the celebrations are less formal, being marked by military gun salutes at several locations in Britain.

This year's Trooping the Color took place as usual with a march by foot soldiers from Wellington Barracks next to Buckingham Palace to Horseguards Parade on Whitehall, the government district of London, where the Queen inspected the troops.

A senior military official, Field Marshal Guthrie, who took part in the parade, was injured when the horse he was riding threw him off on the way back from the parade ground to the barracks.

Field Marshal Guthrie, aged 79, is currently the most senior British military official, and he remains in the army despite having retired from active service in 2001. British media reported that he was being treated in a hospital in London.

The parade concluded with a gun salute in London's Hyde Park by World War I field guns fired by the King's Troop, Royal Horse Artillery and a flypast over Buckingham Palace of aircraft from the Royal Air Force (RAF).