The White House on Sunday said President Barack Obama had informed Congress he authorized U.S. airstrikes in Iraq to help retake control of the Mosul Dam, Reuters reported.
"The failure of the Mosul Dam could threaten the lives of large numbers of civilians, threaten U.S. personnel and facilities - including the U.S. embassy in Baghdad - and prevent the Iraqi government from providing critical services to the Iraqi populace," the White House said in a statement quoted by the news agency.
"These operations are limited in their nature, duration, and scope and are being undertaken in coordination with and at the request of the government of Iraq," added the statement.
The Mosul Dam fell under the control of Islamic State (IS, formerly ISIS) jihadists earlier this month. Control of the dam, Iraq's biggest, could give the Sunni fundamentalists the ability to flood cities and cut off vital water and electricity supplies.
The U.S. Central Command said on Sunday the United States conducted a second day of air strikes against Islamic State fighters near the dam, using a mix of fighter, bomber, attack and remotely-piloted aircraft.
On Saturday, the military confirmed it conducted nine airstrikes near Arbil and Iraq's largest dam in an effort to help Kurdish forces retake it from the IS.
The Islamic State, which has declared a caliphate in parts of Iraq and Syria it captured, forced tens of thousands of Yazidis and Christians to flee their homes or face certain death.