Global bidders are expected to contest this week fr the right to buy a painting of a bare-chested boxer by the renowned artist Peter Howson.

Bid are expected from around the world when the Scottish artist's work, The Sublime and the Ridiculous" is sold at Lyon & Turnbull in the capital on Wednesday.

Dating back to 1989, the huge 8x7ft canvas is based on the artist's walks around Culzean Bay in South Ayrshire.

It portrays his iconic muscular man flanked by a dwarf making a fascist salute and a figure crucified upside down.

The artwork will be sold at the auction house's sale of Contemporary and Post-War Art and is due to fetch between £20,000 and £30,000.

Charlotte Riordan, Lyon & Turnbull's paintings specialist, said: "This immense canvas depicting one of Howson's distinctive characters, fills one wall of the sale-room.

"His depictions of a strong working-class, predominantly masculine world are favoured by celebrity collectors such as Madonna, Mick Jagger and David Bowie.

"They have also featured on a range of album covers for bands including The Beautiful South.

"It is a popular painting and we have already had calls from interested buyers from across Europe, Russia, the USA and Far East."

Howson, who was born in London to Scottish parents, moved to Prestwick, Ayrshire, aged four.

Howson trained at Glasgow School of Art alongside contemporaries including fellow figurative artists Ken Currie, Steven Campbell and Adrian Wiszniewski.

Having spent a short time in the Royal Highland Fusiliers during the 1970s, he was commissioned by the Imperial War Museum of London to be the official war artist for the 1993 Bosnian Civil War and later the official war painter at the Kosovo War for the London Times.

He was recognised with an OBE in the 2009 Birthday Honours, and his work has been collected by celebrities from Madonna, Bowie and Jagger to Bob Geldof and actor Robbie Coltrane.

The huge central figure in The Sublime and The Ridiculous, it has been reported, represents the soldier or common man who follows orders, while the dwarf with his fascist salute is based on dictatorial examples of misguided power. The crucified figure is said to symbolise molested innocence.

Howson said in 1989, shortly after its completion: "It is the first of a series of cliff paintings based on the walks around Culzean Bay. I wanted to move in to the landscape, get more light in to my pictures.

"It would have been all too easy to set the events in an urban night-time situation. I have loved Culzean since art school days and over the years spent a lot of time there."