US aircraft pounded the insurgent bastion of Fallujah on Sunday, killing at least 14 people.
The US army said in a statement that Iraq's interim government had authorised "a strike against a known terrorist fighting position in southern Fallujah".
Around 25 fighters loyal to Jordanian militant Abu Mussab al-Zarqawi were in the area just before the attack, it said.
The air strike, at around 2 am (2200 GMT on Saturday), "destroyed defensive fighting positions and trench lines near the remains of a house and a foreign fighter checkpoint", the US military said.