Iraq's most influential cleric has urged Iraqis to vote in favour of the draft constitution in Saturday's referendum.
The backing of Grand Ayatollah Ali al-Sistani, who has great influence over the 60 per cent of Iraqis who are Shia Muslims, came as political leaders stepped up their efforts to prevent the vote causing a deepening of sectarian hatred.
"Sayyed Sistani has called on Iraqis to vote Yes," his aide told Reuters. Although the Iranian-born cleric distances himself from politics, Iraqi politicians often seek his advice.
Meanwhile Iraqi political leaders have agreed to make changes in the constitution three days before the vote. In a hastily negotiated compromise the Shia and the Kurds agreed that, even after the constitution is approved, it can still be amended by a newly elected parliament next year.
The changes came after intense pressure from US officials fearful that the new federal constitution will increase support for the resistance from the Sunni Arabs. The Sunni have denounced it as a recipe for breaking up Iraq into Shia, Kurdish and Sunni cantons.
"I have good news for the Iraqi people on this historic day," said President Jalal Talabani. "An agreement has been reached on amendments to the draft constitution. There is no excuse for Arab Sunnis to boycott the vote."
The UN is supposedly distributing five million copies of the constitution, but few Iraqis say they have received copies. Officials now say voters will be informed by television on what they are voting for.
The Iraqi Islamic Party, which claims a considerable following among Sunni Arabs, said it now approved of the constitution. But the Sunni leaders involved in the negotiations may represent little support on the ground. "This is a ploy by the people in power to divide the Sunnis, " said Hussein al-Falluji, a Sunni politician. "Anyone supporting this constitution is merely ruining his reputation," said Abdul Salam al-Kubaisi of the influential Muslim Clerics Association.
Iraq continued to be convulsed by violence. A suicide bomber blew himself up near an army recruitment centre in the northern city of Tal Afar, killing 30 people. There was an attempt to kill Saad Naif al-Hardan, the minister for provincial affairs, in Baghdad when a suicide bomber drove into a convoy of guards which was about to pick him up. Further west in Ramadi, insurgents have threatened to kill anyone who goes to the polls on Saturday. Police reports say that 425 Iraqis have died violently in the past 17 days but this understates the real figure.
The amendments to the constitution would in theory give Sunni Arab members of a new National Assembly, to be elected on 15 December, the power to introduce radical changes. But these changes would have to be ratified by a two-thirds vote in parliament and a second referendum. Given that the Shia and Kurds are 80 per cent of the population this is unlikely.