LONDON - Practice makes perfect: Kate Middleton and her bridesmaids, together with best man Prince Harry, rehearsed one more time at Westminster Abbey on Thursday, the eve of the most anticipated royal wedding in decades.
The rehearsal came as Middleton and Prince William released their wedding program, which says they have been deeply touched by an outpouring of affection toward them.
"We are both so delighted that you are able to join us in celebrating what we hope will be one of the happiest days of our lives," they wrote. "The affection shown to us by so many people during our engagement has been incredibly moving and has touched us both deeply."
They also released a new photograph by celebrity photographer Mario Testino - a warm black-and-white image.
Much is at stake for the royal family, who hope the match bolsters the Windsor dynasty and smooths over memories of the damaging, embarrassing divorce of William's parents, Princess Diana and Prince Charles. William has often referred to his late mother with great affection and gave Kate his mother's engagement ring - ensuring she isn't forgotten during the sacred occasion.
The ceremony was to offer pomp and circumstance on a scale to rival Charles and Diana's fairy-tale wedding in 1981, with 1,900 invited guests and royal carriages drawn by mounted troops of the Household Calvary. Rows of bold red, white and blue Union Jacks have been unfurled in the streets and cleaners have scrubbed the parade route.
Tens of thousands of people are expected to line the twisting path from Westminster Abbey to Buckingham Palace, where the new royal couple will appear on the balcony for a kiss watched by millions around the world.
Westminster Abbey itself has been transformed into a blooming forest, with six field maples and two hornbeams lining the aisle leading up to the altar.
Dozens of die-hard fans were already camped out in tents and sleeping bags Thursday near the iconic landmark. Among them was India Marlow-Prince, a 17-year-old from London who was picnicking with friends. The trio painted their faces with the Union Jack and wore tiaras and matching hot pink T-shirts with the homemade slogan "Will and Kate forever."
"She is the Diana of our generation. And Wills is a babe," Marlow-Prince said. "We are a little annoyed at her for taking him, but there's always Harry."
The wedding presents a major security challenge for the 5,000 police officers on duty, who will be on the lookout for Irish dissident terrorists, Muslim extremists, anti-monarchists, protesters and hooligans. A wide range of police will be on patrol: officers on motorcycles, escort specialists, dog handlers, search officers, mounted police, protection officers and firearms units.
Scotland Yard Police Commander Christine Jones said there has been no new terror threat but considerable Internet chatter. "Our operation has been meticulously planned, and we have thought through and planned for a huge range of contingencies," she said.
But it wouldn't be a wedding without a tussle over the guest list. Britain revoked a royal wedding invitation to Syrian Ambassador Sami Khiyami because of violent attacks on protesters by the regime there.
More than 450 people have been killed since mid-March in the uprising against President Bashar Assad's authoritarian regime, with 120 dead over the weekend.
Royal families from Bahrain, Bhutan, Brunei, Kuwait, Lesotho, Oman, Qatar, Saudi Arabia and Swaziland have been invited to the wedding, prompting the anti-monarchy Republic group to call the guest list "a Who's Who of tyrants and their cronies."
Critics also questioned why there was room for despots in the abbey while former British prime ministers Gordon Brown and Tony Blair, both from the Labour Party, were omitted.
Prime Minister David Cameron called the event a moment of celebration amid a period of tough austerity measures. His Conservative-led government is carrying out 81 billion pounds ($135 million) in spending cuts through 2015, slashing hundreds of thousands of government jobs and sharply hiking tuition fees.
The wedding will bring "happiness and joy and light relief after some difficult times," Cameron told Katie Couric on CBS.
"British people ... feel very deeply about the monarchy and the institution, so it's that mixture of the good-looking prince and the beautiful princess, but it's so much more than that," Cameron said. "It's this institution that's helped bind the country together. And it's got this amazing history that goes way, way back."
Middleton will not promise to "obey" her new husband in her vows but instead to "love, comfort, honor and keep" him.
She will walk up the aisle to the sounds of "I was glad," the anthem setting of Psalm 122 composed by Sir Charles Hubert Hastings Parry for the coronation of King Edward VII in 1902. The anthem was also sung at the 1981 wedding of William's parents.
The hymns - "Guide me, O thou great redeemer," "Love divine, all loves excelling" and "Jerusalem" - are standards at Church of England marriage ceremonies.
"Guide me, O thou great redeemer" was also the final hymn at Diana's funeral in Westminster Abbey in 1997.
The newlyweds will leave to the march "Crown Imperial" by William Walton, which also figured in Charles and Diana's wedding.
A spokesman at St. James' Palace said Middleton was familiar with classical music but had "a lot of input" from Prince Charles. "They spent a a lot of time listening to the music together on iPods," said the royal functionary, speaking on condition of anonymity.
But as wedding excitement heated up, the weather in London started cooling down. Royal wedding fans may want to pack extra umbrellas.
The Meteorological Office says the day will start off gray and dry with low clouds across London. Some sunny spells may break through but the chance of showers will rise to 30 percent around noon, the time when William and Kate will emerge from the Abbey a newly married couple.
Associated Press Writers Sylvia Hui, Paisley Dodds, David Stringer, Jill Lawless, Robert Barr and Aaron Edwards contributed to this story.