U.S. command said the toll included nine Army soldiers and two Marines.
Four soldiers were killed in separate small-arms-fire attacks Monday in Baghdad. Four more died when a roadside bomb blew up as their patrol passed by northwest of the city. The ninth soldier was killed Sunday when his vehicle was hit by a roadside bomb.
The military also reported that two more Marines have been killed, both in fighting in western Iraq's dangerous Anbar province. One was killed Sunday. The other died Saturday. They were among five Marines killed over the weekend: four in combat, one in a vehicle accident. More than 2,700 members of the U.S. military have lost their lives in Iraq since the war began.
In other developments:
The government of Prime Minister Nouri al-Maliki has been under intense pressure to put an end to Shiite-Sunni violence that has killed thousands of people this year. This week, gunmen carried out two mass kidnappings in as many days, snatching 38 people from their workplaces in Baghdad — attacks that Sunnis said were carried out by Shiite militias.
Monday night, al-Maliki announced a new four-point plan aimed at uniting the sharply divided Shiite and Sunni parties in his government behind security efforts to stop the bloodshed.
The parties have long been blaming each other for the killings.
Sunnis accuse the Shiite-led security forces of turning a blind eye to killing of Sunnis by Shiite militias — some of which are linked to parties in the government. Sunnis have accused al-Maliki, a Shiite, of being hesitant to crack down on the militias.
Shiites, meanwhile, accused Sunni parties of links to terrorists after a bodyguard of a Sunni party leader, Adnan al-Dulaimi, was arrested by U.S. forces on Friday and accused of plotting al Qaeda bombings.
The four-point plan, signed by all sides, aims to resolve disputes by giving every party a voice in how security forces operate against violence on a neighborhood by neighborhood level.