BEST-SELLING author Irvine Welsh to to write the script for a radical adaptation of one of the classics of romantic medieval fiction by Sir Walter Scott.

Welsh, whose most famous book remains Trainspotting, is to the write the script for what has been described as a "bold new adaptation" of Ivanhoe, in a new project that will bring together two of the Scottish capital's most famous literary sons.

The film is to be directed by Jon S Baird, who also directed Filth, a film adaptation of Welsh's novel of the same name that starred James McAvoy.

The movie is to be produced by Jens Meurer, based in Berlin, who also worked on Filth, according to a report on the Deadline film website.

Ivanhoe is a historical novel by Sir Walter Scott, first published in 1820 in three volumes and subtitled A Romance. Ivanhoe, and is set in 12th-century England.

It tells the tale of one of the last Saxon noble families in a time when the Normans were rapidly becoming the dominant ruling class of the feudal state.

The hero is Wilfred of Ivanhoe and is set in 1194, after the failure of the Third Crusade, when many of the Crusaders were still returning to their homes in Europe.

Robin Hood appears in the tale, although under the name of Locksley, in a role which helped portray Hood as a cheery hero surrounded by 'merry men'.

Scott's Ivanhoe was credited with popularising the middle ages as a backdrop for literary adventures.

The novel features much medieval combat and a notable jousting tournament, and nearly all of the action takes place in England.

Scott's character is carved on the side of the Scott Monument in Princes Street Gardens in Edinburgh.

Ivanhoe is not a stranger to the big screen, or to television.

Its most famous filmic iteration was in 1952 when a movie version included Elizabeth Taylor, Joan Fontaine, George Sanders and Robert Taylor as Ivanhoe.

A report said that in Welsh's version, "Ivanhoe and his fellow returning knights suffering to different degrees from Post Traumatic Stress Disorder following their ultimately failed exploits against Saladin and his successful recapturing of Jerusalem."

Other film versions of Ivanhoe included films in 1911 and 1913, and there have been several TV versions of the story.

The 1952 Ivanhoe was nominated for three Oscars.

A Soviet version of the story was made in 1983, The Ballad of the Valiant Knight Ivanhoe.

Several of Welsh's books have made it to the big screen. The most famous is Trainspotting which made stars of Ewan McGregor and Robert Carlyle but Ecstasy and The Acid House were also adapted.

Welsh is to appear at this year's Glasgow book festival, Aye Write! where he will talk about his new novel, A Decent Ride.

The book, about a bawdy Edinburgh taxi driver, has been described as "funniest, filthiest book yet".

He said: "Glaswegians; they are some of the funniest, most generous people you could ever wish to meet.

"I'm looking forward to reading from my latest novel A Decent Ride in Glasgow and seeing what they make of Juice Terry [its central character]."

Aye Write! is now in its 10th edition and will take place at Glasgow's Mitchell Library from April 17-25.