More than three years after Warner Brothers acquired the film rights for the book in a deal said to be worth $1m, a spokesperson for the studios in Burbank, California, told the Sunday Tribune that the project has yet to be approved for production.

In October 2004, Richard La Gravenese, the director of The Horse Whisperer and The Bridges of Madison County, was slated to direct the film, while Wendy Finerman, producer of Forest Gump and the woman who first spotted the manuscript's movie potential, was on board as a coproducer. At the time, Ahern said she would like to see Jennifer Aniston take the lead role, though casting was never confirmed.

But since then, according to Warner's, the project has been stalled. "There hasn't been any movement on it; there's nothing happening at this point, " said the spokesperson. "It hasn't been green lighted." Warner Brothers, in common with most large film studios, option far more film projects than it ever develops.

But while PS, I Love You appears to have slipped off Warner's radar in its Burbank headquarters, back in Dublin, Marianne Gunn O'Connor, the literary agent who secured dizzy deals for the Taoiseach's younger daughter's first novel when she was still only 20, insists the project is very much alive. "It's not true that there's nothing happening, " she said, "in fact, we're very close to making a major announcement on it. Whoever you spoke to in Warner's got it wrong."

While she declined to elaborate on developments in the project last week . . . "as soon as I have the green light, I'll be issuing a press release" . . . Gunn O'Connor was adamant that PS, I Love You does have a future in film. A dramatised version of the novel . . . which concerns a 30 year old widow whose husband leaves her a series of letters which instruct her on how to rebuild her life after his death . . . was broadcast by BBC Radio 4 last year. Meanwhile, Ahern's most recent novel, If They Could See Me Now, has been optioned by Disney for a film starring Hugh Jackman . . . a project that Gunn O'Connor is also bullish about.

In the three years since Ahern first stormed the publishing world with multimillion euro deals, she's more than proved worth the punt, having clocked up sales of more than 5m worldwide for her three novels. If You Could See Me Now followed its predecessors onto the best-sellers' lists in Britain and in Ireland and made the extended bestsellers list of The New York Times.

The 24-year-old now ranks amongst the world's best selling authors and has amassed a considerable personal fortune for her work. Two years ago, she bought a 1.5 million penthouse apartment close to her mother Miriam's home in Malahide.

The Sunday Tribune understands that Ahern recently put the property on the market, though her next move is unclear.

One thing is certain: if she's planning to upgrade, then a green light on PS, I Love Yo u would be most welcome . . . her deal with Warner's includes a $500,000 payment on the first day of shooting.