The US aid administrator says the international community should work together to rebuild the Iraqi marshlands damaged by Saddam Hussein.
Andrew Natsios, the USAid boss whose agency has the lead responsibility for the physical reconstruction of Iraq, says the rebuilding of the Iraqi marshlands should be a high priority for the United States, the new Iraqi government, and the international aid agencies.
The disaster has hit the Marsh Arabs who rely on the waterways
He told a meeting in Washington that "we are with you" and said USAid had been examining the situation in the Iraqi marshlands since the autumn.
But he stressed the daunting nature of the task, which would involve redesigning the water system, the relocation of hundreds of thousands of people, and a huge investment of scientific and practical resources.
The unique ecosystem of southern Iraq constitutes the largest wetlands in west Asia, and were the home to up to 400,000 Marsh Arabs who had occupied the area for 5,000 years.
This is the area of southern Iraq where the rivers Tigris and Euphrates join, and is thought by some to be the original site of the Garden of Eden.
But the area of the marshes has been shrinking, and has almost disappeared - with less than 15% of the original marshland still intact.
Saddam Hussein deliberately drained the marshes as a tool of oppression against the marsh people, his political opponents, and to clear the way for his tanks to advance during the Iran-Iraq war.
After the 1991 uprising by Shia Muslims, they were also the target of military oppression designed to drive them from their homes.
About 50,000 are refugees in Iran, and it is believed that up to 200,000 were internally displaced in Iraq.
Baroness Emma Nicholson, the British member of the European Parliament who has taken up their cause, says she was told by tribal leaders in southern Iraq last week that up to 200,000 Marsh Arabs were still living in immediate vicinity of their former homes.
However, the task of restoring their former habitat will face huge political and physical problems.
Experts like Thomas Naff of the University of Pennsylvania believe that only some of the marshlands can be restored, mainly those bordering Iran.
And to do so would put more pressure on the fragile river systems of the region, whose flow has already been greatly diminished by dams, irrigation schemes, and the fluctuations in flow, he said.
The problem has an international dimension, as dams upstream in Turkey and Syria have also reduced the flow of the rivers into Iraq.
It is feared that new Turkish dams planned for the River Tigris, including the controversial Ilusu project, could make the situation worse.
There is no international agreement with Turkey over regulating the flows from the dams, with Syria and Iraq asking for 50% more water volume than the Turks are prepared to supply.
And Peter Galbraith, the former US ambassador to Croatia, points out another political problem within a new Iraq.
He says the emergence of a federal system in Iraq, with a weak central government, could mean that upstream provinces, especially in Kurdish areas, might be reluctant to share water with the Marsh Arabs.
Victor Tanner of Johns Hopkins University, an expert on internal displacement, points out that the Marsh Arabs might not have much political clout within Iraq society, as they are a marginalised group even within the Shia community - and might require support from the international community to get their case heard.
Complicating matters further is the fact that huge oil fields lie under the marshes, with estimated production of 3m barrels per year, equal to Iraq's current total production.
Building the infrastructure of roads, power lines, and oil pipelines would further undermine the fragile ecology of the marshes, according to Professor Naff.
Convincing the Iraqi people that the US is not motivated by Iraq's oil reserves is crucial to restoring political authority in Iraq, Mr Galbraith argues.
And, according to Emma Nicholson, the world community bears a heavy responsibility for the ecological and human disaster in the marshlands.
"We watched it happen. We had the power, the knowledge and the responsibility and we did nothing," she said.