The US was criticised for not stopping the looting
US Attorney General John Ashcroft has vowed to track down thieves who took priceless artefacts from Iraqi museums during the chaos of the war.
"Regardless of how sophisticated these criminals are... the US law enforcement and our colleagues at Interpol will not rest until the stolen Iraqi artefacts are returned to their rightful place: the public museums and libraries of Iraq," he told a conference on the thefts organised by Interpol in Lyon, France, on Tuesday.
Iraq's National Museum, which held thousands of artefacts from ancient Mesopotamia, one of the world's earliest civilisations, was looted along with other institutions as US-led forces toppled Saddam Hussein's regime in April.
The looting has been described as "the crime of the century" and the US military has been accused of not doing enough to stop it.
Mr Ashcroft said there was strong evidence that the looting had been steered by organised criminal groups "who knew precisely what they were looking for".
"Although the criminals who committed the thefts may have transported the objects beyond Iraq's borders, they should know
that they have not escaped the reach of justice," he told the conference on its second and final day.
The US has reportedly prepared a United Nations Security Council resolution asking nations to be on the
alert for, and to return, any stolen Iraqi objects.
Interpol Secretary General Ronald Noble said a priority
would be to build a reliable database of stolen or destroyed items.
We don't yet have a complete record of all the stolen objects
Giovanni Boccardi, Unesco
Investigators, customs officials and dealers could use the massive database.
"One of the key proposals is to significantly expand Interpol's existing database of stolen art to include the thousands of other items now missing in Iraq," said a statement from Interpol.
The UN cultural agency Unesco and the International Council of Museums also attended the Lyon conference.
Working out what exactly is missing is a major task for investigators.
Museum inventories, which may have been incomplete to start with, were destroyed or lost during the looting.
"We don't yet have a complete record of all the stolen objects, and we don't have any means to verify that a certain object is indeed coming from that collection," said Giovanni Boccardi from Unesco's World Heritage Centre in Paris.
The US military has begun broadcasting radio messages offering rewards to Iraqis to return the antiquities.
More than 100 items have already been handed in, US Central Command said last week.
They are said to include priceless manuscripts, a 7,000-year-old vase and one of the oldest bronze bas-relief representations of a bull.
Leading international experts in Mesopotamian antiquities, who met in London last week, have called for a further tightening up of Iraq's borders to stop looted items being smuggling out of the country.