RAMADI: At least 13 people were killed on Thursday in an air assault by US forces on a house in Iraq's restive city of Ramadi, medics said.

"US planes bombed a house in Aziziyah area of Ramadi city centre, killing 13 civilians," Ali al-Obeidi, a medic at the Ramadi hospital said, adding that four people were wounded.

The US military confirmed it had conducted the assault but did not give casualty figures.

Last month, US marines waged a fierce firefight with rebels who attacked government headquarters in Ramadi with car bombs, rockets and machine guns.