UN Secretary General Kofi Annan has urged Iraq's interim government to reach out to the Sunni Muslim minority ahead of the 30 January elections.
Annan: Conditions for election are "far from ideal"
He said it was vital to include the "Arab nationalist" part of society in order to ensure the vote contributed positively to political transition.
The UN secretary general also said preparations for the poll had been very fair and efficient.
In Iraq violence in the build-up to the election continues unabated.
- Late on Thursday gunmen shot dead another member of Iraq's electoral commission near Baghdad, an interior ministry official told the AFP news agency on Friday.
- Kurdish officials form the Kurdish Democratic Party said that gunmen killed three members of the party in an ambush in the northern city of Mosul. The incident occurred on Thursday but was only reported on Friday.
- The US military confirmed that three of its soldiers died in violence on Thursday. Two US Marines were killed in the western Anbar, and a soldier died near the city of Mosul.
Not ideal conditions
Mr Annan conceded that it was clear the conditions in which the voting was being held were far from ideal, and it was obvious there would be attempts at intimidation and further violence.
The secretary general said it was clear that the vast majority of Iraqis were eager to exercise their democratic right to vote.
More than 1,000 US soldiers have died in action in Iraq
"I have always made clear that the elections must be as inclusive as possible, if, as I hope, they are to contribute positively to the political transition in Iraq," Mr Annan said.
"Even at this late stage, reaching out to the Arab nationalist component of society, especially the Sunni Arabs, is critical to this. I encourage the government to intensify its efforts in this direction."
Powell urges voting
Mr Annan's comments echoed those of US Secretary of State Colin Powell who said elections in Iraq will be a success if they are representative of the whole country, including the Sunni Muslim minority.
But he warned that if Iraqis did not take part, that would embolden the insurgents.
The White House has acknowledged that there is likely to be intimidation of voters, particularly in Sunni areas.
Meanwhile a retired US Army General Gary Luck has arrived in Iraq to review the security situation, and assess the development of Iraqi security forces.
In a separate development, Nato says it is considering scaling down plans for its training mission in Iraq.
The alliance's top commander, General James Jones, said the proposed reduction was because Iraq's own forces could now do more training themselves, and Nato did not want to send more instructors than it had to.
General Jones said the training mission had not been helped by the refusal of some countries to send troops.
About 100 Nato instructors and support staff are currently in Iraq - lower than the target of 300 personnel which was suggested last month.