The 15 October referendum on a constitution opposed by some Sunni Arabs as a recipe for division is expected to pass, but officials have been recounting the ballots in some areas because of unusually high yes or no totals.
On Monday, Sunni Arab lawmaker Mishaan al-Jubouri claimed fraud had occurred in the vote - including instances of voting in hotly contested regions by pro-constitution Shia Muslims from other areas - repeating earlier claims of election-fixing made by other Sunni Muslim officials over the weekend.
Asked whether the result would be announced on Friday, Adil al-Lami, one of seven commissioners on the Independent Electoral Commission of Iraq (IECI), said: "No, definitely not today. And perhaps not even tomorrow. I can't say exactly when it will be."
He said initial figures on turnout showed that across the country 64% of voters had cast their ballot. However, turnout had been much lower in the province of al-Anbar, the focus of Sunni Arab fighting, with only 32% turning up on polling day.
Turnout in Baghdad was 56%, he added.