The Queen is no longer planning to attend the Epsom Derby during her Platinum Jubilee weekend.

The 96-year-old monarch is said to want to pace herself during the milestone celebrations, with the Princess Royal representing her at the racecourse instead, The Sunday Times reported.

The Derby on Saturday, June 4 was to be a personal highlight for the Queen during the four days of Jubilee festivities.

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A passionate horse owner and breeder, the Queen was due to be greeted on the course with a special guard of honour including up to 40 of her past and present jockeys.

However, The Sunday Times revealed the monarch is now “increasingly unlikely” to head to Epsom.

Buckingham Palace declined to comment, saying the Queen’s attendance at events would not be confirmed until closer to the time.

News Shopper: Artist impression of the stages outside Buckingham Palace (BBC/PA)Artist impression of the stages outside Buckingham Palace (BBC/PA)

The nation’s longest reigning monarch, who is on a pre-Jubilee break resting in Balmoral, Scotland, has reportedly been facing mobility problems in recent months.

This led her to miss a number of major events this year, including the State Opening of Parliament.

She is, however, expected to please crowds with a double appearance on the Buckingham Palace balcony – at the start of the celebrations after Trooping the Colour on Thursday, and after the Pageant parade finale on Sunday.

The monarch is also hoping to be able to attend the service of thanksgiving at St Paul’s Cathedral on Friday, with her wider family including, it is expected, the Duke and Duchess of Sussex and the Duke of York.

On Sunday, thousands of people will gather across the country as more than 85,000 Big Jubilee Lunches and street parties are staged in celebration of the Queen’s record-breaking 70 year reign.

In a personal message ahead of the celebrations, Prime Minister Boris Johnson has praised the monarch’s leadership, wisdom and lifelong service.

“With the first Platinum Jubilee ever, no monarch has ever served the country so long and, more importantly, no monarch has ever served it so well,” Mr Johnson said.

“Providing leadership and wisdom, this remarkable woman has dedicated her life to serving her people and to her beloved Commonwealth.

“She has led this country through good times and bad, inspiring people to serve others and their communities to create the pride and allegiance that unites us all.”