Diplomats from the Arab League are flying to Iraq to prepare the ground for a conference on bridging the country's deep divisions.
Violence continues across Iraq as the referendum approaches
The envoys from the 22-member organisation are under instructions to listen to all sides and to avoid any appearance of being partisan.
Iraq holds a constitutional referendum next week as discord continues between its Shia and Sunni Muslim communities.
The Arab League's leader told the BBC he believed it was close to civil war.
"The situation is so tense... a civil war could erupt at any moment although some people would say it is already there," Amr Moussa told BBC radio's Today programme.
"There are a lot of individuals... now playing games with the future of Iraq and there is no clear strategy, there is no clear leadership."
The Arab League, he said, would work to bring Iraq's different religious and ethnic groups together.
In other developments:
- The Pentagon announces the end of its Iron Fist operation to track down insurgents in Anbar province, reporting the death of more than 50 Islamist militants and at least six US marines; two US soldiers were shot dead on Friday as another operation, River Gate, continued in Anbar
- Sunni associations meeting in Baghdad unite in calling for voters to reject the constitution but do not agree on an outright boycott of the referendum
- Insurgents carry out new gun and bomb attacks across the country on Saturday, killing a local politician and a seven-year-old boy near Kirkuk and a police captain in western Baghdad, Iraqi police said.
Mr Moussa's assistant for political affairs, Ahmed bin Hilli, is leading the Arab League team on the five-day visit.
Attacks on civilians on all sides have grown sharply
It will be a tough job given the depth of the divisions, the BBC's Heba Saleh reports from Cairo, where the league is based.
The diplomats have been instructed to speak little and to listen to all sides, as well as avoiding any sectarian disputes and maintaining good relations with all groups.
The aim is to help forge a consensus on the new Iraqi constitution and to ensure the participation of all Iraqis in the political process.
It is not clear, however, if it will be possible to organise the reconciliation conference before Iraqis vote in the referendum on 15 October.
Mr Moussa is also due to visit Iraq some time this month and is expected to chair the conference on his first trip to the country since the fall of Saddam Hussein.
Our correspondent notes that Arab governments, whether acting individually or collectively through the Arab League, wield little influence in Iraq.
However, they are deeply concerned that the descent into chaos there could prove unstoppable and that it will have negative repercussions for the whole region.