Queen Elizabeth plans to break with tradition at this year's Royal Ascot

A courtier told the Daily Mail newspaper: "It's the end of an era.

Carriages are no longer possible for Her Majesty. It's not the ride that's the problem, but the steep steps that are needed to get into and down from the landau."

Royal Ascot typically begins with the Queen and other members of her family arriving from Windsor in horse-drawn landaus. They then watch the races from the Royal Enclosure.

The only time the Queen has previously broken the tradition was when she was pregnant.

Meanwhile, Queen Elizabeth's never-seen-before home movies are set to feature in a new BBC documentary.

The monarch's life will be the focus of 'Elizabeth: The Unseen Queen', a 75-minute documentary that will include behind-the-scenes footage from landmark moments in her reign.

Simon Young, the BBC's commissioning editor for history, recently said:

"This documentary is an extraordinary glimpse into a deeply personal side of the royal family that is rarely seen, and it's wonderful to be able to share it with the nation as we mark her Platinum Jubilee."

Claire Popplewell, the creative director for BBC Studio Events Productions, believes the upcoming documentary will be "special", and she can't wait for people to see the family footage.

She said: "As programme-makers who have previously worked closely with the Royal Household on ceremonial and celebratory broadcast events and programmes, the production team were under no illusion quite how special having access to this very personal archive was.

"Being able to draw upon the self-recorded history of a young Princess Elizabeth and her wider family - and allowing the Queen to tell us her own story - is the very heart of this film."