The sequel to 90s blockbuster Trainspotting will start shooting in Scotland in May, actor Robert Carlyle has revealed.

Carlyle, who plays Begbie in both movies, said the script for the new film is "absolutely fantastic" and stronger than the first film.

The actor joined author Irvine Welsh at The Usher Hall in Edinburgh to mark 20 years since the original movie.

Carlyle said: "We start shooting, I understand, in the middle of May and I think it's going to be pretty much 50-50 between Edinburgh and Glasgow.

"I'm basing this on nothing other than the fact that the production office is on Bathgate. There's a clue there.

"What I will say is that all the characters are exactly where you would want them to be. The strength of this new script is the fact that the narrative is a bit stronger than it was in the original.

"In the first one, when you think about it, it's hard to remember what they did other than get together, the drug deal at the end, and then it's over.

"This has maybe got a wee bit more to it in terms of what they've been up to through these years.

"You learn a lot about Renton, Sick Boy and indeed Begbie and where their heads are. I think it's an absolutely fantastic script. John Hodge has done a wonderful job, as he did with the original.

"Fingers crossed people will take it on board and they will enjoy it."

The pair also predicted the sequel will contain a nod to the original movie's Britpop, punk and house soundtrack. Welsh revealed he was initially sceptical about 1990s Britpop artists featuring in a movie based on his book about 1980s Edinburgh drug culture.

Carlyle said: "Without giving anything away, there's a moment in the script where Renton goes to his room back in Edinburgh, which hasn't changed from back in the day.

"He goes to his record collection and has a flick through, and I imagine you will see some of the titles. "When I read the screenplay last year I was very moved by that. It was quite emotional because this music is as much part of the soundtrack of my life as the film's.

"It's in there but I genuinely don't know what Danny's (Danny Boyle) plans are with the music. There will be a nod to it, I would imagine."

Welsh said: "A lot of the artists like Iggy Pop, Lou Reed and some of the house stuff was in the book, but I couldn't really see the Britpop stuff working.

"I was completely wrong about that. The genius of the original soundtrack was it gave it a sense of place, a sense of time, and helped make it into such an iconic film.

"It was so low budget that I was about getting artists that we knew involved, and basically give us something for nothing to licence the tracks."