Most of the antiquities on sale in Britain are either stolen or fakes, a leading museum scientist has told a national conference on art crime.
Paul Craddock, a scientist at the British Museum whose work involves checking the authenticity of artefacts, said international legislation had so far "proved toothless" at fighting the burgeoning problem.
"The amount of legitimate material on the market is very, very small," Dr Craddock said. "Most antiquities on the market nowadays are either stolen or forgeries."
The claim at a conference in London organised by the Fraud Advisory Panel could prove highly damaging to the lucrative London market.
The British art market is believed to be worth more than £500m a year and in 2000 the Metropolitan Police alone seized £22m worth of stolen or faked antiquities.
Looting a problem dating back centuries is also a modern phenomenon, as demonstrated by the widespread theft of artefacts after the invasion of Iraq two years ago.
Dr Craddock's comments prompted protests from some of the dozens of delegates. Ros Wright, chairman of the Fraud Advisory Panel, established by the Institute of Chartered Accountants, said: "I'm sure that nobody does take away the impression that all art on the market is suspect."
Art and auction houses in London have spent several years tightening security and the Cultural Objects Offences Act of 2003 made it illegal to trade in goods thought to be tainted. Auction houses are as liable as banks for making sure that they are not being used to launder suspect money and figures from the Art Loss Register, the London-based company with a database of 160,000 stolen items, suggest the number of stolen works being sold at auction has fallen.
But Dr Craddock insisted the scale of the problem was such that he would want clear evidence of an object's history before he bought anything himself.
He cited the example of an unnamed American heiress who amassed a sizeable collection of Middle Eastern jewellery in just two years. When it was taken to a museum, most of it was shown to be fake.
One of the most famous fakes acquired by the British Museum was the Crystal Skull, supposedly an Aztec symbol of death, bought in 1897. Recent analysis showed it was cut and polished with a type of rotating wheel used in 19th century Europe.
Alexandra Smith, of the Art Loss Register, said the scale of looting was shrouded in mystery. "It is terribly difficult to tell how many works of art are stolen because a lot of people never report the theft," she said. "One museum abroad was recently reported to have lost 300 paintings, but failed to tell anyone because they were so embarrassed."Reuse content