The nephew of Andy Warhol has said he believes a 'miracle' discovery is not the work of his uncle.
The sketch was bought for £3 by West Country entrepreneur Andy Fields at a car boot sale near his holiday home in Las Vegas. He claimed it could be Warhol's first step into pop art. He said it was sketched by the artist as an 11-year-old schoolboy while living in Pittsburgh PA.
The drawing is of the head of Rudy Vallee on a colour-chequered background. It is signed 'Andy Warhol.'
Warhol would later become world-famous for his pictures of soup tins and silkscreens of Marilyn Monroe.
One expert backed Mr Fields' claims and gave the piece an estimated price tag of 2.1 million dollars.
During his research into the picture, Mr Fields contacted James Warhola, who is the son of Warhol's brother Paul. Mr Warhola says he thinks the picture is not original.
But Mr Warhola, who lives in Baltimore, MD, says his uncle would not have signed the work 'Warhol' as he didn't drop the 'A' from his surname until later.
He also said the style of the drawing doesn't match other examples of Warhol's work.
Mr Fields' work was presented to the Andy Warhol Authentication Panel last year. The panel did not approve the picture - saying it needed more information about the sketch's background. But it did not completely reject the picture either. The panel has since disbanded.
The sketch is going on public display at the Royal West of England Academy next month. It is part of a drawing competition run by Avon & Somerset Police to try to occupy children during the Summer.
Mr Fields said he has always been open about the doubt that surrounds the work, he says he will continue to research the background of the sketch to establish if it is genuine.
Watch Rob Murphy's full report, including an exclusive interview with Andy Warhol's nephew: