Tintin's new screenwriter says filmmakers are still discussing which story will form the basis of the sequel.
Anthony Horowitz said earlier this year that he had penned a script based partly on Herge's Tintin story Prisoners Of The Sun.
But he told the BBC: "That was true a few months ago but I can tell you that I think the second film is not going to be Prisoners Of The Sun... What it is going to be is still under discussion."
The writer said: "I've had meetings with the directors and producers and we've talked about ideas and action sequences.
"At the moment I'm trying to put together a story that will please everybody. It's a very difficult one to do."
The screenplay for Steven Spielberg's first Tintin film, The Adventures Of Tintin, starring Jamie Bell, Daniel Craig and Andy Serkis, was written by Steven Moffat, Edgar Wright and Joe Cornish.
Anthony, the writer of the Alex Rider series of spy novels, is set to pen the Tintin sequel directed by Peter Jackson.