One is by Britain's best-known modern artist, who has amassed a huge fortune by selling his notorious works for up to £1.5 million. The other has been churned out for years by an unknown who, every Sunday, sells his paintings for less than £100 each from a pavement pitch on the Bayswater Road.

But the works by Damien Hirst and Talaat Elshaabiny are intriguingly similar and both are uncannily like an obscure Christmas card design which predates them both.

Entitled Spirit, Hirst's painting of a dove soaring against a sky-blue background is one of the works in his latest exhibition. It went up for sale three months ago at his Hoxton gallery for an undisclosed, six-figure sum.

Mr Elshaabiny, who is not represented by a gallery, has been selling his version for four years.

This is not the first time Hirst has produced a work of art that turned out to be less than original.

Hymn, his enormous bronze sculpture of a skinned human figure, had already been snapped up by Charles Saatchi for £1 million when it emerged the statue was remarkably similar - except in size - to a £14.99 children's anatomical science model produced by the company Humbrol.

Earlier this year the Evening Standard revealed Hirst had created another statue, Charity, based closely on the once ubiquitous collection boxes for Scope, formerly known as the Spastics Society.

But Hirst has never claimed to be worried about what people think of his art. As early as 1990 he was quoted as saying: "I can't wait to get into a position to make really bad art and get away with it. At the moment if I did certain things people would look at it, consider it, and then say, 'Eff off '. But after a while you can get away with things."

It is not known what precisely inspired Hirst to paint his dove, but Mr Elshaabiny readily admits his version is based on a Christmas card he received from a friend almost a decade ago.

He said: "I liked the image of the dove, so I decided to keep hold of it for a painting. I keep repeating it because people seem to like it so much."

The dove has long been used to represent the Holy Spirit, depicted as such by artists including van Eyck (Ghent Altarpiece), Fra Filippo Lippi (The Annunciation), and Jan Gossaert (The Adoration Of The Three Kings).

A curator from the V&A examined the dove image as painted by Hirst, Mr Elshaabiny and the unknown artist behind that Christmas card, but could not identify any one precise source.

Egyptian-born Mr Elshaabiny, who moved to Britain 18 years ago, said his painting comes in three sizes and is one of his best sellers.

He first learned of Hirst's dove from a customer. "He asked if I knew there was another painting very like this by a famous artist on sale for a lot of money. I didn't." The customer bought Mr Elshaabiny's dove for the usual £75.

Mr Elshaabiny is not resentful that Hirst can knock out what is very nearly the same image and sell it for so much. "He's famous. And of course he has the right to paint the picture. If I were famous I would ask the same price. But I am poor and work on Bayswater Road."

He admits he is no aficionado of Hirst's work: "Modern art really isn't to my taste. I prefer the classics, like da Vinci."

Hirst's views on Mr Elshaabiny's work are not known.

Mr Elshaabiny's other paintings on sale every Sunday include a litter of playful rottweiler pups, a couple walking hand in hand along a sun-dappled beach and a sunset over the Houses of Parliament.

"But of all the paintings the dove is my favourite," he said.