LONDON (AP) _ Princess Diana's funeral is still two days away, but carpenter Martin McCann has already staked out a place outside Westminster Abbey.

``I am here to pay the respects due to Princess Diana,'' said the 44-year-old unemployed Londoner, who intends to remain at the abbey until Saturday's service.

``She has lost her life and I am only going to lose about three days _ it's not that much of a sacrifice,'' said McCann, who arrived at lunch time Wednesday wearing a black T-shirt and jeans and carrying a suitcase containing more black clothing and some food.

Buckingham Palace is still finalizing details on the funeral, which is expected to draw crowds in the millions, according to revised estimates by police in London.

Diana's two sons, William, 15, and Harry, 12, may decide only at the last moment if they want to walk in their mother's funeral procession, Buckingham Palace said. ``It will entirely depend on Princes William and Harry,'' said a spokesman, speaking on customary anonymity.

They return to London on Friday from the royal family's Scottish home at Balmoral Castle with their father, Prince Charles, to pay their last respects to their mother, who is lying in the Chapel Royal at St. James' Palace.

Diana, 36, who was divorced from Charles a year ago, died early Sunday in a car crash in Paris that also claimed the lives of her companion Dodi Fayed, 42, and their chauffeur. A bodyguard survived.

Driven by a massive outpouring of public grief, Buckingham Palace on Wednesday more than tripled the length of the funeral procession, adding 2 1/2 miles to the original one-mile route through central London to Westminster Abbey.

``It is important there is a longer route so we can have as many people able to participate,'' said Prime Minister Tony Blair, who spoke to Prince Charles by telephone Wednesday.

The coffin, borne by a gun carriage, will leave Saturday from Diana's Kensington Palace home instead of St. James' Palace, as had previously been planned.

In an attempt to deflect crowds from Westminster, Buckingham Palace said, two giant TV screens in Hyde Park will show the proceedings live. The Palace also announced the 77-mile route the coffin will follow northward to Diana's home village for burial.

Blair, his deputy John Prescott and three former prime ministers will be part of a small group of politicians attending what Buckingham Palace has called ``a unique ceremony for a unique person.''

Few other guests have yet been named for what is likely to be one of the biggest public events of the decade.