LONDON, DEC. 9 -- Prime Minister John Major announced today that Prince Charles and Princess Diana will separate, effectively ending what had begun as a storybook marriage and raising the likelihood that Britain will have competing his-and-her royal courts with wildly contrasting styles.

Major, who set aside his preparations for a crucial European Community summit to announce the royal breakup, told the House of Commons that the decision by the couple to lead separate lives had "no constitutional implications."

But it clearly did have implications for the royal House of Windsor, buffeted by seemingly endless scandal and controversy. What had once seemed an archetypal family, raised above others by regal distance, now seemed more common and as confused by the complexities of modern life as anyone else.

Charles, whose title is Prince of Wales, will remain heir to the throne currently held by his mother, Queen Elizabeth II, Major said. The couple's two young sons, William and Harry, retain their places in the line of succession.

And as far as Diana is concerned, Major said, "There is no reason why the Princess of Wales should not be crowned queen in due course." That statement envisioned a king and queen occupying separate palaces and holding separate courts.

Buckingham Palace said the prince and princess had "no plans to divorce." They will both participate in the children's upbringing, a palace statement said, and "from time to time attend family occasions and national events together."

But the days of pretending are over. Charles, 44, will occupy the couple's country home at Highgrove, also using apartments at London's Clarence House. Diana, 31, and her court will reside in London at Kensington Palace, handy to the trendy restaurants and shops she favors.

Experts who follow royal affairs agree that Diana, with her flash and style, is by far the most popular member of the family. Her public appearances always draw large, enthusiastic crowds. The dour Charles attracts few.

While the timing of today's announcement was a surprise, it had been apparent for months that Charles and Diana were just going through the motions of a marriage.

First came the publication of a scandalous biography of Diana -- in which she is thought to have cooperated -- depicting Charles as an unfeeling cad who had driven his lovely young wife to attempt suicide. Then came the release of taped phone conversation in which a male admirer breathed heavily into Diana's ear and called her "Squidgy." Weeks later came another tape in which Charles and an old flame, Camilla Parker-Bowles, passionately professed their love for each other, reportedly discussing their "private parts."

The British monarch still has a constitutional role, although largely a ceremonial one, to play -- opening Parliament, summoning and dissolving governments, consulting each week with the prime minister.

It was because of that continuing role that Major canceled a key meeting with European Commission chief Jacques Delors -- at which the two men were to plan for a watershed European Community summit, beginning Friday in Edinburgh -- in order to tell the House of Commons of the royal separation.

The tribulations of Charles and Diana were hardly the only royal news this year. Princess Anne, the queen's only daughter, was divorced and has announced plans to remarry. Prince Andrew, the queen's second son, was separated from his wife. Andrew's estranged wife, the former Sarah Ferguson -- known as "Fergie" -- was caught cavorting topless with her American "financial adviser" in the south of France. The queen's favorite residence, Windsor Castle, was seriously damaged in a fire.

Queen Elizabeth herself, under unprecedented public pressure, agreed to start paying income tax. In a speech after the Windsor Castle fire, she called 1992 an "annus horribilis" -- a horrible year -- and pleaded with the relentless British media to have a little compassion.

But reminders of scandals past keep cropping up. Just today, "Fergie" was awarded damages of nearly $100,000 by a French court, which ruled that the photographer who snapped the topless shots of her St. Tropez interlude had violated her privacy. This Saturday, Princess Anne is scheduled to embark on her second marriage -- only she plans to hold the wedding in Scotland, since the Church of England, which her mother heads, disapproves of remarriage.

Buckingham Palace sources said the announcement of the separation, which steals thunder from Princess Anne's impending wedding, was made today to minimize the disruption for the couple's children, Princes William and Harry. Both boys begin their Christmas breaks from school this weekend, and the aim was to clarify the situation before the holiday season.

According to sources, the final decision to separate was made in the last two weeks. Major had separate meetings with Charles and Diana, the sources said, adding that the prince and princess remain "fond of one another."

The announcement caused new speculation about whether Charles will ever become king. His mother, at 66, is in robust health and has made clear that she considers being queen a job for life.

The notion has been raised that Charles, with his messy personal life and the prospect of being an old man when he finally takes the throne, would ask to be skipped in the line of succession in favor of his son William, now 10. The London bookmaker William Hill tonight quoted odds of 6 to 1 against Charles renouncing the throne -- down from 10 to 1.

"What I think we've seen is the beginning of a long saga in which they finally skip a generation," said Parliament Member Tony Banks of the opposition Labor Party. "I can't see Prince Charles becoming King Charles."

According to Buckingham Palace spokesmen, the archbishop of Canterbury has said that the separation does not affect Charles's ability to serve as head of the Church of England. Royalty watchers say, however, that a divorce might have an impact on his church role.

Reaction to the separation was generally sympathetic. Sir Edward Heath, a former Conservative Party prime minister, said that Major's statement "must be one of the saddest announcements made by any prime minister in recent times," and he urged understanding by the public and the media.

John Smith, the Labor Party leader, said he is certain the entire House of Commons "will share the feeling of sadness."

But Labor MP Dennis Skinner, a sharp-tongued critic of the monarchy, was in no mood to be generous. "It's high time we stopped this charade of swearing allegiance to the queen and her heirs and successors, when we do not know from time to time who they are," Skinner said in the House of Commons, drawing catcalls.

The Charles and Diana fairy tale began on July 19, 1981, when the Prince of Wales married a shy 20-year-old with a dazzling smile, Lady Diana Spencer, in a glittering ceremony at St. Paul's Cathedral in the heart of London. She was the first royal bride to omit the word "obey" from her marriage vows.

At first overshadowed by her older, more confident husband, Diana grew in self-assurance and political skill. The public could not get enough of her, as she developed an intriguing personal style and carved out a niche for herself as a spokesman for various causes, especially AIDS research and care.

Over the years, it became obvious that the marriage had lost its spark. But the crowning blow came this spring, when author Andrew Morton published a book called "Diana: Her True Story" that portrayed the princess as a young woman trapped in a loveless marriage. The book said she despaired of Charles's continuing relationship with Parker-Bowles, who is married to one of his best friends, and claimed she suffers from the eating disorder bulimia and had attempted suicide several times.

It was clear that Diana's friends had cooperated with Morton in his research for the book, and Charles's supporters came to suspect that Diana herself had played a role. The voracious London tabloids reported that the prince and his parents were angry but faced with a problem -- Diana had developed her own persona, her own constituency.

After the Morton book, the couple appeared together infrequently. During a recent tour of South Korea, billed by Buckingham Palace as a "reconciliation tour," they were so hard-pressed to smile in each other's presence that reporters dubbed them "the Glums."

Now she will have her own palace, her own courtiers, her own life.

The queen and her husband, Prince Philip, were said to be saddened by the separation. Diana went about her duties today, visiting a school near Newcastle. Charles, making an appearance tonight after the announcement, strode into London's historic Guildhall with a big grin on his face.