Downton Abbey creator Julian Fellowes has said filming a big screen version of the period drama would begin immediately if it were up to him.
The hit ITV show came to a close on Christmas Day in 2015 but has since sparked speculation about returning with a film.
Arriving at the Olivier Awards nominees luncheon, where his show School Of Rock is vying for prizes, Lord Fellowes told the Press Association: " If it were up to me I would answer immediately and we would go this afternoon but it's not my choice and not my decision."
He said he thinks the fact the show created such big stars will make it harder for the film to come together, because the actors are scattered around the world working on other projects.
Lord Fellowes said: "I'm pro it, I'm not resisting but logistically I think it's quite hard because it's a very big cast and you would want to get all of them, or pretty well all of them, and they are all on Broadway or in Hollywood and so on and we would have to find this magic window."
However, he added he is delighted to have made household names of so many young talents, including Lily James, Michelle Dockery and Laura Carmichael.
Lord Fellowes said: "With the young, you find them and a lot of this business is luck. You have to have some ability but there are plenty of people with a lot of ability who never get a lucky break and if you can be that lucky break it's very rewarding."
Earlier Phyllis Logan , who played housekeeper Mrs Hughes in Downton, told Good Morning Britain: "The will is definitely there with everybody involved."
She added: "Fingers crossed that we can make it all come about at some stage. And we'd love to get back together again and have one last hurrah."
But the Scottish actress, who is currently starring in The Good Karma Hospital, said it would not be easy to reunite all the cast and crew in one place.
"There's so many of us," she said, adding: "In normal film situations you might have a core cast of half a dozen or whatever. But this is a core cast of thousands, it feels like at times. And so ... herding cats?"
Her comments come after Jim Carter, who played butler Carson, hinted that a movie spin-off could be close.
Carter, whose alter-ego married Mrs Hughes in the show, previously said "nobody's seen the script" but that the cast had been asked to keep dates free for the big screen version.
"There's a place in the West Country called Julian Fellowes's head and it's in there somewhere. I'm sure it will emerge," he said.
The final episode of Downton Abbey was the most watched TV show on Christmas Day in 2015.