Iraqi negotiators are locked in last-ditch efforts to persuade disgruntled Sunni Arabs to sign a draft constitution after missing a third deadline for a parliamentary vote.
Negotiators in Baghdad Friday say federalism, including Shi'ite demands for a mini-state in the south, remains the main obstacle.
Sunni leaders say a federal structure will rob them of the country's oil-wealth, largely concentrated in the Shi'ite south and Kurdish north. They have warned of civil war if the constitution goes through as it is currently written.
The speaker of Iraq's parliament says the current draft constitution will be put to voters in an October 15th referendum unless a compromise is reached in the next few days.
Although the constitution requires only a simple majority in the referendum, the charter will be defeated if two-thirds of voters in any three of Iraq's 18 provinces vote against it.