Now it has turned into one of the country’s biggest literary spats with some of Scotland’s best-known writers lining up on both sides – some taking pot shots at Kelman, others backing the outspoken novelist.

Kelman, a Booker Prize winner, made his blistering attack at the Edinburgh Book Festival by deriding Scotland’s obsession with “upper middle-class young magicians” and “f****** detective fiction”. He went on to target the whole of the Scottish literary establishment.

Singling out this country’s failure to embrace its “radical traditions” and its insistence on doling out praise to “mediocre” writers, he bemoaned a commercialised literary scene in thrall to Harry Potter and Rebus.

“If the Nobel Prize came from Scotland they would give it to a writer of f****** detective fiction, or else some kind of child writer, or something that was not even new when Enid Blyton was writing The Faraway Tree, because she was writing about some upper middle-class young magician or some f****** crap,” he said.

Contemporary literature, he said, was “derided and sneered at by the Scottish literary establishment” who were “Anglocentric” and bent on ignoring the edgier talent that is right under their noses – citing poet Tom Leonard as an example of one such cruelly marginalised Scot.

The outburst has caused bitter divisions in the normally sedate Scottish world of letters. Chief among the opponents of Kelman’s position is Michael Schmidt, an acclaimed poet and writer as well as the founder of Carcanet Press, the editor of the PN Review, and professor of poetry at Glasgow University, as well as the convenor of the university’s prestigious creative writing programme.

Schmidt said: “His whole approach does sound exceedingly Stalinist. It so disparages the common reader. People who like Rankin and the Harry Potter books genuinely read them for pleasure.

“We all hate the commercialisation of literature, but Ian Rankin writes very competently and the Harry Potter books are very entertaining. I don’t know if we should feel they are in any way degrading to the high culture we find ourselves participating in and advocating.”

Schmidt also claimed Kelman cannot get excited about new writers, instead constantly name-checking friends in his close circle, made up exclusively of working-class Glaswegians.

Schmidt added: “When you get a really major figure like Alistair Gray, you don’t see him fulminating like this. Instead, you find him a very generous spirit excited by new writing. He does not surround himself with rancour.

“There is a parochialism that says Scotland first, and there is an internal parochialism that says Glasgow first, and then Glasgow working-class first. Each time you get into a smaller parochialism, the more authoritarian the feel of the language is.”

Kelman’s main target was so-called “genre fiction” – writing that sticks to well-known conventions, such as the detective story – and generally avoids experimentation with form or language. Many fear genre fiction is now Scotland’s greatest literary export, crowding out more cutting-edge work.

John Byrne, the writer of the recently re-released television hit Tutti Frutti, said: “I subscribe to James’s complaint or observation, because there is a danger of Scotland becoming known as the home of genre fiction, a factory churning out these things. And it’s much easier to make that sort of stuff than write deep, literary fiction. Maybe it needs someone like Jim Kelman to set the cat among the pigeons and have us all up in arms.”

Alan Bissett, a celebrated young author, said: “I have sympathy with Kelman. What he seems to be saying is mediocre writing – by which he means genre writing – is given undue attention by the Scottish literary establishment. Also, the commercial success of certain titles and writers is distorting the view from outside Scotland of what Scottish writing is, just how hard edged and radical it can be.

“Kelman comes from a pure place and sees that commercial fiction is inevitably controlled and dominated by market forces, pushed on us by publishers and booksellers because they know it will sell. What some people might see as snobbery is simply Kelman trying to fight for a space in mainstream culture for radical voices.”

However, Bissett did identify one of Kelman’s “blind spots”: his failure to recognise the skill of genre authors like Ian Rankin or Denise Mina.

Another fact ignored by Kelman is that highly commerical fiction, such as the Harry Potter series, often bankrolls more serious work.

Rodge Glass last year published a weighty tome called Alasdair Gray: A Secretary’s Biography with Bloomsbury and contends that if it was not for the same publishing house’s success with JK Rowling they would not have had the cash to put his book out.

Nevertheless, Glass agreed with most of Kelman’s comments.

“There is something to be said about the sanitising of Scottish history, thought and literature for people coming in who want a nice, easy story. Homecoming Scotland and the profile of Burns has affected the profile of everyone else that is writing in Scotland. What it appears Kelman has said, and I don’t want to speak for him, is there is a scene that is being ignored and I back him in that. He has been very brave with these remarks.”

Scottish crime writer Denise Mina, however, was far from taking Kelman’s side in the row. Writing today in the Sunday Herald, she says: “Kelman is a beautiful writer and I love his books, but this debate actually drives readers toward genre fiction. It’s like the prefects looking down on the juniors ... People in the arts are more concerned than anyone about status. And that’s what this is: a play for status.”

When the Sunday Herald spoke to Kelman, he refused to be quoted in full – simply stating he did not care a jot about the furore he had created.