The cast of Trainspotting's long-awaited sequel have reunited in Edinburgh on Sunday for the film's world premiere.

The showing of T2 Trainspotting, which sees the return of original cast members Ewan McGregor, Robert Carlyle, Jonny Lee Miller and Ewen Bremner, as well as director Danny Boyle, is being held at Cineworld, Fountain Park.

The stars were greeted by the crowds as they walked the orange carpet ahead of the showing, which was also attended by Trainspotting original cast member Kelly Macdonald and Anjela Nedyalkova - who plays the lead female character Veronika in T2.

Ewan McGregor described reuniting with his fellow Trainspotting stars to reprise their original characters in the sequel as an "amazing" experience.

The actor also said he has done the best work of his career for director Danny Boyle, with whom he still has a "wonderful dynamic".

McGregor said: "It is quite daunting to come back to a character who is so well known and loved. Like all of the characters in Trainspotting, they are people who we feel like we know.

"They are like people who we have really met in life - Begbie, Sickboy, Spud and Diane. It was sort of daunting, but I am Renton, and Renton is me.

"I haven't lived in Scotland since I was 17 years old and there was a sort of trepidation about coming back, thinking maybe I don't have it any more, but then Renton hasn't been in Scotland for 20 years either because he's been in Amsterdam, so our stories are not dissimilar I guess."

McGregor, who made his international breakthrough with the first film, spoke fondly of reuniting with Boyle and his castmates, despite not having seen some of them in the intervening years.

He said: "It was very lovely to work with Danny again. I didn't feel like that had changed. The dynamic there was wonderful, and I found him to be a director who pushes you.

"He is somebody I have done my best work for, I think he pulls great work out of actors. He knows how to do that somehow."

T2 comes 21 years after the first film, which followed a group of heroin addicts and explored urban poverty in Scotland's capital.

It is based on the novel of the same name by Irvine Welsh, with the sequel based on his book Porno.

Early reviews suggest the film has won over most critics - although all agree it can never leave the same legacy as the original.

The Guardian's Peter Bradshaw describes the film as "scary, funny, desperately sad, with many a bold visual flourish", while The Herald's Rob Carnevale calls it "an emotional rollercoaster that seldom lets up for the near two-hour running time".

Set in the present day, the main characters - Renton (McGregor), Sick Boy (Jonny Lee Miller), Spud (Ewen Bremner) and Begbie (Robert Carlyle) are now middle-aged.

The trailer for the sequel was released in November and opened with Renton returning to Edinburgh to see his friends again.

Over the strains of Underworld's hit Born Slippy, which featured prominently in the 1996 film, he revives his bitter "choose life" motto but with modern references - "Choose Facebook, choose Twitter, choose Instagram and hope that someone, somewhere, cares".

He also refers to choosing reality TV, slut-shaming, revenge porn and zero-hour contracts before saying: "Choose to smother the pain with an unknown dose of an unknown drug."

Renton's narration ends with: "You're an addict, so be addicted, just be addicted to something else. Choose the ones you love, choose your future, choose life."

The cast and crew from the new film were seen filming at various locations across Edinburgh and elsewhere in Scotland in 2016.

In July, McGregor and Bremner were seen sprinting out of a shop on Princes Street, with Oscar-winner Boyle directing the pair as they recreated the famous opening sequence from the first movie.

T2 Trainspotting will be released in UK cinemas on January 27.