US Secretary of State, Condoleezza Rice, has said the US will stay committed to what it hopes will be an inclusive Iraq.
Ms Rice made an unannounced visit, her second to Iraq this year, during which she said she wanted help ease the sectarian tensions that have dominated the campaign for a parliamentary election on 15 December.
Three Iraqi policemen on patrol were wounded when a car bomb exploded in a central area of Baghdad within minutes of Rice's arrival in the capital's heavily fortified Green Zone.
She said her goal was to urge Iraqis to bridge sectarian and ethnic divisions and create a single country where all felt 'fully protected'.
Ms Rice said Washington would support no particular candidate next month, despite complaints from some that US officials are working behind the scenes to favour certain groupings.
Sectarian tension between Saddam Hussein's once-dominant Sunni Arab minority and the Shi'ite and Kurdish-led government have dominated the election campaign.
Earlier, attacks continued with three policemen being killed and two wounded when gunmen aboard a minibus machine-gunned a checkpoint in Baquba north of Baghdad.
The violence flared a day after suicide bombers struck a restaurant and an army recruiting station, killing 37 people, with the bloodiest attack claimed by the Al-Qaeda group led by Jordanian militant Abu Musab al-Zarqawi.
