One of London's most famous thoroughfares will stage a street party next year to mark the Queen's patronage of more than 600 charities and organisations.
The Queen is said to be excited by the prospect of 10,000 guests joining herself the Duke of Edinburgh, Duke of Cambridge and Prince Harry in The Mall for the sit-down celebration.
The Patron's Lunch will honour the monarch's lifetime dedication to service and will be the culmination of a weekend of national events next summer marking the monarch's official 90th birthday.
A service of thanksgiving attended by the Queen and Philip will be held at St Paul's Cathedral on Friday, June 10, the following day the traditional Trooping the Colour ceremony, also known as the Queen's Birthday Parade, will be staged in Horse Guards Parade and on the Sunday the street party.
Peter Phillips, the Queen's grandson, is helping to organise the street party in his role as director of Sports Entertainment Ltd, a global events agency which came up with the idea for The Mall street party.
Mr Phillips told the Press Association: "We wanted to create a celebration based off the back of the successful Golden Jubilee and Diamond Jubilee where there was a ground swell of warmth and affection for the Queen."
But he stressed next year's celebration would have more of an emphasis on the Queen's support for her charities: "We want to reflect the service she's given to all her organisations and charities."
He added: "And insure there was a suitable celebration of her commitment to her patronages and provide the opportunity for her patronages and other communities around the country to say thank you."
Guests will enjoy a hamper-style lunch along the length of The Mall, with entertainment and Union flags adding to the atmosphere and William and Harry acting as joint presidents of the event.
Mr Phillips said about his grandmother: "She's obviously been kept abreast through her office about all the developments and the times I've had the chance to talk to her (about it) she's been excited by it."
Members of the public will also be able to share in the festivities at live sites situated in Green Park and St James's Park.
The not-for-profit event will also raise money for a newly created Patron's Fund, which will be used to support specific initiatives and projects run by the Queen's charities.
The Queen is patron of a wide range of organisations from Barnardo's and Battersea Dogs and Cats Home to the British Diabetic Association and Great Ormond Street Hospital.
The monarch also has an official role with organisations in the Commonwealth like the Australian Medical Association, Canadian Red Cross Society and the New Zealand Medical Association.
The organisers hope communities around the country will be inspired to stage Patron's Lunches in their own areas and raise money for local projects.
Adventurer Bear Grylls, chief scout of the Scout Association which has the Queen as its patron, said: "This year 500,000 Scouts will be following her example and supporting communities with our Million Hands project.
"We look forward to celebrating not only on The Mall, but right across the United Kingdom. As Chief Scout I would like to say a huge thanks to The Queen. Let's make her proud."