Trainspotting 2 will be loosely based on Porno, the follow-up novel by Irvine Walsh, author of Trainspotting.

The original movie, a brutal saga of heroin addiction and desperation set in Edinburgh, starred Ewan McGregor, Robert Carlyle, Jonny Lee Miller and Ewen Bremner.

Speaking at Colorado's Telluride Film Festival, Boyle told Deadline Hollywood the principal cast members were keen to sign on again.

"All the four main actors want to come back and do it," he said. "Now it is only a matter of getting all their schedules together which is complicated by two of them doing American TV series."

The possibility of a sequel has been rumoured for years but the main stumbling block was a long-standing rift between Boyle and McGregor, which has since been smoothed over.

Next year will mark the 20th anniversary of the release of the cult classic, which was voted best-ever Scottish film in 2004.