The U.S. Embassy in Iraq has issued evacuation recommendations it says could help save up to 1.5 million lives at risk from the possible collapse of the Mosul Dam in northern Iraq.
Concern has grown in recent months about the deteriorating condition of the dam, which is the largest in the country.
If the dam collapsed, it would unleash a wave that would devastate the city of Mosul and flood much of the capital, Baghdad, more than 450 kilometers to the south.
The dam was built on an unstable foundation that continuously erodes.
A lapse in required maintenance after the dam was briefly seized by Islamic State militants in 2014 has further weakened the already flawed structure.
The U.S. Embassy said it had no specific information about when a breach might occur.
But it said as many as 1.47 million Iraqis living in exposed areas along the Tigris River probably would not survive unless they are promptly evacuated if the dam collapses.