The college romance that seemed to falter in the harsh glare of adulthood has blossomed at last, promising Britain its biggest royal wedding since Prince Charles married Lady Diana Spencer almost 30 years ago.
Royal officials announced Tuesday that Prince William and Kate Middleton will marry next spring or summer in London, ending years of rumored splits, reconciliations and will-they, wont-they speculation.
Charles' Clarence House office said the heir to the British throne was "delighted to announce the engagement of Prince William to Miss Catherine Middleton." It said the couple got engaged last month during a vacation in Kenya.
William's grandmother, Queen Elizabeth II, and her husband Prince Philip "are absolutely delighted for them both," Buckingham Palace said.
Prime Minister David Cameron was delighted, too, wishing the couple "great joy in their life together." He said he announced the news during a Cabinet meeting, and it was greeted by cheers and "a great banging of the table."
The news was not, however, a surprise. Kate and William's engagement was the safest bet in Britain, considered so certain that bookies had stopped taking bets on a 2011 wedding. The date avoids London's Summer Olympics and the queen's Diamond Jubilee, both being held in 2012.
"We thought it was going to happen, now that it has it's an opportunity for a welcome national celebration," said Patrick Jephson, former secretary to Princess Diana, adding that her son's nuptials would be "a masterclass" in wedding planning.
No venue has been announced yet. For pomp itself, the ceremony is likely to fall between the extraordinary spectacle of Charles and Diana's 1981 wedding in St. Paul's Cathedral and Charles' subdued second marriage to Camilla, Duchess of Cornwall at Windsor Guildhall in 2005.
William, who is second in line to the throne after Charles, once told an interviewer he wouldn't marry "until I'm at least 28 or maybe 30." He turned 28 in June.
Middleton, also 28, met William at the University of St. Andrews in Scotland. They shared a student house in the seaside university town, where William initially studied art history before switching to geography.
In 2002, William paid 200 pounds to sit in the front row at a charity fashion show where Middleton was modeling in a daring outfit -- they are thought to have started dating the following year.
A wealthy commoner rather than an aristocrat, Middleton is the daughter of self-made millionaires. Her father worked for an airline and her mother was a flight attendant before they started a mail-order business specializing in children's parties, run from their house in southern England.
She attended Marlborough College, an elite private school, where she played tennis and field hockey, before studying art history at St. Andrews. After graduating in 2005, Middleton worked for a time as a buyer for the fashion chain Jigsaw. She is now employed by her family's party-planning business.
The couple's relationship became public with a joint photo on a Swiss skiing holiday in 2004. Middleton then became a media darling -- especially after both graduated, ending a media agreement to leave William alone while he was at university. With her confident good looks and long brown hair, Middleton became one of the most photographed women in Britain.
The brunette fashion buyer was photographed attending public events, going to work, even getting a parking ticket -- a level of attention that evoked the romance of William's parents, Charles and Diana.
Middleton was there when William was commissioned as a British Army officer after graduating from Sandhurst military college in 2006.
William was determined that Middleton would not suffer the same media hounding endured by his mother, who died in a Paris car crash in 1997. He appealed through his office for the media to leave her alone.
In 2007, Middleton filed a harassment complaint against a British newspaper. She accepted an apology and admission of error from the Daily Mirror.
It was widely thought the couple would soon announce their engagement. The retail chain Woolworths even commissioned mugs, plates and other Wills-and-Kate memorabilia.
But only weeks later in 2007, media reported -- and Clarence House did not deny -- that the couple had broken up. Newspapers pored over the apparent end of the relationship in long stories sourced to anonymous "friends." William's army training kept them apart, said some. The media pressure was too much for her, said others. Still others murmured that senior courtiers felt Middleton's middle-class background wasn't royal material.
Soon, however, the same newspapers were reporting that the pair had rekindled their romance. They were photographed leaving a London nightclub together, and Middleton was snapped on a stag hunting expedition at the royal family's Balmoral estate alongside Prince Charles.
When William graduated from his first flying course in the spring of 2008, Middleton applauded from the sidelines -- although his training was not without incident. The Ministry of Defense confirmed that William had landed a helicopter on Middleton's parents' lawn during a training flight and flew a Chinook to a friend's stag party on the Isle of Wight.
William later served a two-month deployment with the Royal Navy before training to become a Sea King search-and-rescue pilot with the Royal Air Force. He recently completed that training.
The pair have recently seen each other mostly on weekends, with William a frequent visitor to the Middleton family house in the affluent village of Bucklebury, 50 miles (80 kilometers) west of London.
Earlier this month, Middleton's parents were invited to join members of the royal family for a shooting holiday at Balmoral -- the queen's estate in Scotland -- another milestone on Kate's road to acceptance by the royal family's inner circle.
Clarence House said after the wedding, the couple will live in north Wales, where William is based with the RAF.
The couple were to give their first joint interview later Tuesday. Middleton has rarely, if ever, spoken about William in public.
"I love the uniform. It's so, so sexy," -- her assessment at William's graduation from Sandhurst -- was a rare slip.
Gregory Katz in London contributed to this report.