Gun salutes mark Queen's 88th birthday

Soldiers from the Honourable Artillery Company fire a 62 round royal gun salute to celebrate the 88th birthday of Britain's Queen Elizabeth II at the Tower of London in central London. Photo / AFP

The Queen's 88th birthday has been marked with traditional gun salutes.

The King's Troop Royal Horse Artillery fired the 41-gun royal salute from Green Park in central London at midday, using six 13-pounder First World War guns drawn by 71 horses.

An hour later the Honourable Artillery Company fired a 62-gun royal salute from Tower Wharf by the Tower of London.

The Queen spent the day privately at Windsor Castle, a Buckingham Palace spokeswoman said.

Princess Elizabeth Alexandra Mary was born at 2.40am on April 21, 1926 - the first child of the then Duke and Duchess of York - at 17 Bruton Street, the Mayfair home of her mother's parents, the Earl and Countess of Strathmore.

She is the great-great-grandchild of Queen Victoria, the last female sovereign.

The Queen has two birthdays - her actual one on April 21 and her official one in June, which is celebrated with the Trooping the Colour parade.

A portrait of the Queen by renowned British photographer David Bailey was released on Sunday ahead of her 88th birthday.

The photograph of the monarch, smiling, was taken at Buckingham Palace in March and commissioned on behalf of the Government's GREAT Britain campaign.

The Queen is wearing pearls and a dress by Angela Kelly, who has served as personal assistant and senior dresser to her since 2002.

- AAP