Many have laid flowers, toys and photographs at the gates of her former home.

It is understood that instead of clearing the tributes daily, park officials will leave them for another week.

The princess died with Dodi Fayed and his chauffeur when their car crashed in a road tunnel in Paris on 31 August 1997.

Visitors have also left candles, toys and photographs

It is thought her family will mark the anniversary with a low-key remembrance. Her sons, William and Harry, will be at Balmoral, the Queen's Scottish home.

The princess's brother, Earl Spencer, is expected to spend the day at the family home, Althorp in Northamptonshire, where Diana is buried.

The permanent tribute to Diana at Althorp closed on Monday. Since it opened on 1 July, 142,000 people have visited the exhibition, just 5,000 fewer than when it opened last year.

Call for memorial

Organisers said hundreds of people had left flowers by the lake where Diana is buried.

Many people at Kensington Palace called for a permanent memorial to be put up.

"There's been millions of pounds donated to her fund which has just not been spent and it's terrible," said Anne Shaws, from the Isle of Wight.

Tributes have also been left at the makeshift memorial near where she died in Paris

Joyce Vanherring from Berkshire agreed. "There are not so many people out here this year and it's going to get less and less," she said.

"In the future our children and their children won't know this is the anniversary of her death and we need a memorial to remind people."

People also criticised plans by James Hewitt, the princess's former lover, to publish a book.

Due out later this year or early in 2000, it is widely expected to contain details of his relationship with Diana.

However, Mr Hewitt's lawyer said the love letters written by the princess would not feature in the book.

'Delicate, yet powerful'

A rose commemorating the princess will be launched by the Royal National Rose Society on Tuesday.

The new flower, England's Rose, is a creamy pink colour with an apricot blush.

Its fragrence is described as delicate, yet deceptively powerful.

David Austin, who bred the rose, said: "This is a rose of the greatest delicacy and charm.

"I can think of no rose more suitable to bear Diana, Princess of Wales' name."

About 5000 plants will initially be released.