The Queen yesterday put on a brave face, smiled and told well-wishers: "My mother had a wonderful life."

At Windsor Castle, surveying a sea of flowers left in the Queen Mother's memory, the Queen said: "It's an amazing sight, isn't it? People are so kind."

More than 2,000 bouquets have been placed on the lawn outside St George's Chapel where the Queen Mother's body will be interred on Tuesday.

It was the first time since her mother died on Saturday that the Queen had joined members of the public mourning the royal death.

Speaking to a group of mourners, she said: "My mother lived to 101 which is a great age - she had a wonderful life."

Dressed in black, the Queen spent several minutes with the Duke of Edinburgh looking at the flowers and condolence messages left by people from all over the world.

"They're from everywhere, you know - America, Australia, New Zealand and Canada," the Queen told Philip, who wore a black tie and brown shoes.

The royal couple went inside St George's Chapel, where preparations for Tuesday's private committal service and interment are already under way, to look at a book of condolence which some 7,000 people have signed since Monday.

Earlier, Buckingham Palace announced that Princes William, 19, and Harry, 17, would walk behind their great-grandmother's coffin when it is drawn through the streets of London today in a spectacular military procession.

The sight will bring back memories of the funeral procession for their mother Diana, Princess of Wales, five years ago.

In a break with tradition, the Princess Royal will also join the procession, a ceremony usually reserved for royal men. In all, 14 senior members of the Royal Family will walk behind the coffin on its 28-minute journey from the Queen's Chapel at St James's Palace, central London, to Westminster Hall where the body will lie in state.

They will include the Duke of Edinburgh, the Prince of Wales, the Duke of York and the Earl of Wessex.

Relatives of the Queen Mother from the Bowes Lyon family will also follow the coffin, which will been borne on a gun carriage of the King's Troop Royal Horse Artillery.

With the Earl of Strathmore and Kinghorne, Simon Bowes Lyon and the Hon Albemarle Bowes Lyon will be 15-year-old Lord Glamis, thought to be the youngest person taking part in the procession.

A full-scale rehearsal of the procession was staged yesterday as dawn broke over the streets of the capital.

The 1,600 troops taking part began amassing around St James's Palace in the early hours and the procession began to move at 6am as the sun came up.

In terms of pomp and ceremony, today's procession will be bigger than the royal funeral for Diana, and is the largest pageant of its sort on Britain's streets since the funeral of Sir Winston Churchill in 1965.

Meanwhile, prayers were being said around the clock at the Queen Mother's coffin.

Resting in the historic Queen's Chapel at St James's Palace, the coffin is always attended.

Clergy, led by the Sub Dean of the Chapels Royal, the Reverend Willie Booth, pray from the King James Bible and Book of Common Prayer, the two foundations of the Church of England.

Shrouded in her distinctive royal standard, the coffin of Windsor oak is surmounted by a wreath of pink variegated camellias picked from the Queen Mother's garden at Royal Lodge, Windsor.

On the stone floor, at the head of the coffin, is a potted jasmine plant given to his grandmother by the Prince of Wales as an Easter gift before she died.

The fragrance of beeswax candles mingles with the smell of fresh flowers