Writer explains success of his box office smashes - they are exactly the same film

Three screenwriter Richard Curtis admitted yesterday what many have long suspected: his two greatest film successes, Notting Hill and Four Weddings and a Funeral are the same film.

The man behind four of the top five grossing British films confessed to an audience of comedy writers that he was "disappointed" in himself for the similarity of his work.

Curtis was leading a workshop at Bafta in London with about 150 established writers who had been invited to submit scripts for a series of short films to be shown on Channel 4.

After explaining how he "filled holes" in the script for Four Weddings, expanded the funny bits in Notting Hill and cut out slabs of boring footage from Bridget Jones's Diary, he was asked why he did not branch out from romantic comedies.

He replied: "I'm disappointed in myself. You can't imagine the shock when I realised Notting Hill was exactly the same as Four Weddings and a Funeral; it's Hugh Grant, there are five friends, it's got an American girl who comes in and out of the movie."

The similarity, he claimed, was the result not of a lack of ideas but of him following the most important piece of advice he had for his audience – to write "for yourself and close friends" about something near to your heart.

"I admire and like other movies but they are not the stories that I come up with. You have to go with what is in your bones. Guy Ritchie [writer and director of Lock, Stock and Two Smoking Barrels] clearly hears a different voice and it's a good thing he listens to it."

Other advice offered by Curtis, whose films have taken more than £770m worldwide, was to ignore books about how to write film scripts, be present at every stage of making the film, don't put back jokes once taken out, and make sure the beginning has impact.

The opening sequence of Bridget Jones's Diary when Renee Zellweger gets drunk alone in her flat was originally in the middle of the film until the team realised a long narration planned for the start was simply too boring, he said. The effects of Curtis's tuition will be seen when the winning five films are shown later this year as Reasons to Be Cheerful.