Iraq's Shia-led government on Tuesday ruled out any major change to a draft constitution that parliament looks set to pass this week in the teeth of minority Sunni objections that it could ignite civil war.
"The draft that was submitted is approximately the draft that will be implemented," government spokesman Laith Kubba said after parliament received the text before a midnight deadline. The assembly put off a vote for three days to let tempers cool.
Sunni leaders, who largely shunned a January election that gave Shias and Kurds control of parliament, quickly indicated they would try to mobilise support for a "No" vote in the October referendum on the charter.
The constitution will be rejected if two thirds of voters in three or more of Iraq's 18 provinces vote "No". The Sunnis are a clear majority in at least three provinces in the heartland of the insurgency: Anbar, Salaheddin and Nineveh.
A Sunni delegation met Iraq's Independent Electoral Commission to discuss ways of ensuring participation in those three regions, the commission said in a statement.
President Jalal Talabani, who has brought Iraqi leaders together for weeks in a bid to keep the political process on track and defuse a Sunni insurgency, renewed mediation efforts.
A statement from his office said the Kurdish leader urged all Iraqi sects to unite on the issue of the constitution.
But all sides held fast to their positions.
The Shia head of the parliamentary drafting committee again made clear he did not intend to reopen contentious clauses such as those on autonomous "federal" regions which Arab Sunnis say discriminate against them and could break up the state.
Humam Hamoudi said the Sunni negotiators brought in from outside parliament were not representative and the assembly should now submit the draft to a referendum.
US diplomats, under pressure from Washington to keep Iraqi negotiators to a timetable laid down under American supervision last year, say they will go on working for a consensus that can draw the once-dominant Sunnis away from violent opposition.