Buckingham Palace officials, who have been seeking advice and support from Downing Street in the days since her death, yesterday announced that 500 representatives from her favoured charities will walk as part of the funeral procession, expected to be watched by more than 1 million people on the streets of London.
Many of those following her coffin are expected to be from groups she cared most about; the disabled, children, the elderly and people with HIV or Aids.
In another move designed to meet the extraordinary groundswell of grief - shown again yesterday with massive queues of people signing books of condolence around the country - the palace is considering narrowing the main funeral procession to let more members of the public pay their last respects to the People's Princess.
Immediately after the 11am Westminster Abbey service, the nation will observe one minute's silence, though many other organisations, including British Airways, London Underground, supermarkets and shopping centres will observe an unofficial two minutes' silence at 11am.
The arrangements announced so far partly reflect the influence of Tony Blair and his officials, to whom the Palace turned for advice after Diana's death in a Paris car crash early on Sunday.
From the very start of this tragic week, the Prime Minister has taken the view that he needed to offer the Palace advice on the strength of national grief, and how to provide a release for that deeply emotional reaction.
There was no question of the Prime Minister's office putting pressure on the Palace, but Royal advisers recognised that fresh from his landslide election victory, Mr Blair had a surer feel for the public pulse.
For that reason, when the families, the Palace and Number 10 agreed that the Abbey service should not be packed with the great and good, dignitaries from the world of diplomacy and politics, it was the Prime Ministers' office gave the Palace the confidence to "scythe" the diplomats and the politicians from the congregation.
Three Downing St emissaries were spotted going into the Palace by photographers yesterday and on Monday: Alastair Campbell, the Prime Minister's press secretary and a man with all the populist instincts of a former Mirror political editor; Hilary Coffman, a former Labour Party press officer who helped arrange John Smith's remarkable funeral in 1994; and an unidentified civil servant on the Prime Minister's staff.
But there has been no conflict between the two sides, whose discussions have also taken on board the views of the Spencer family. The Palace was keen to accept the advice not only of Number 10, but also from the princess's office. Yet the idea of the funeral procession - the common touch - was yesterday acknowledged as the Palace's initiative.
A Palace spokesman said the show of national grief was an "accurate reflection of the great respect and affection which the British public had for the Princess of Wales."
Meanwhile charities, including those six whom Diana retained formal links with after "resigning" from more than 90 last year, welcomed the populist form of the procession.
There was, however, confusion among some charities about just whom they were expected to send, workers or beneficiaries.
A number of those approached by The Independent said they were sending staff rather patients, children, or the disabled. A spokeswoman for the Royal Marsden Hospital - of which Diana was president - said it was following Palace advice in sending five members of staff from different departments. Great Ormond Street hospital is also sending workers, pointing out that half its patients are under two years of age.
Hillary Clinton will be among the many representatives of foreign governments attending the funeral.
Meanwhile the outpouring of emotion across the country - and many parts of the world - continued to astonish observers. Police estimate almost 100,000 people a day are visiting Kensington Palace, the Princess's home, to lay tributes.
One police officer surveyed the scene and said: "Kensington Palace has become a garden of remembrance."
At St James's Palace, where Diana's body is lying in the Chapel Royal, the numbers of people queuing to sign the 15 books of condolence - increased from five - were if anything greater than on Monday.Reuse content