Yesterday should have been the first of three days of consensus-building after Parliament delayed a vote on the draft submitted by the Shias in the face of vociferous opposition from the Sunnis, who argued that it could ignite a civil war.

But instead of resuming talks, Shia leaders turned to the media to send their uncompromising message to Sunni negotiators that they should let the Iraqi people vote for or against the document in a referendum.

Human Hamoudi, the Shia head of the constitutional drafting committee, said that there would be no reopening of the most contentious clauses on federalism and that he did not believe that any agreement would be reached within the stipulated three days.

Instead, he said, the draft would be sent barely changed to Parliament, where the comfortable majority enjoyed by the Shias and the Kurds could be expected to vote it through. If the Sunnis did not like that, he added, they could simply vote it down in the referendum, scheduled for October. “The Iraqi people will rule,” he said.

Other Shia negotiators echoed his hardline position, saying that the only compromise they could countenance was a retreat by the Sunnis. “The only possible change now is that the Sunnis become convinced on federalism,” Jalal al-Din al-Sagheer, a Shia cleric on the drafting team, said.

President Bush heaped yet more pressure on the Sunni minority, which had enjoyed patronage and power under Saddam Hussein. He said: “This talk of the Sunnis rising up . . . I mean the Sunnis have got to make a choice — do they want to live in a society that’s free, or do they want to live in violence?” Despite the stalled dialogue, Mr Bush said that “democracy is unfolding” in Iraq.

Laith Kubba, the Iraqi Government’s chief spokesman, confirmed that the strategy was to let voters decide the issue in a referendum.

He said: “The Iraqi people can accept or reject this new constitution. This is a new experiment. The process should be completed.”

Sunni leaders, who gave warning last night of “an uprising in the streets” if Parliament adopted the draft, denounced the Shias for not attempting a consensus within the committee.

Sunni negotiators have complained that they had been shut out of negotiations as Shias and Kurds met on their own.

“We haven’t been in any meetings yet,” Saleh al-Mutlak, a leading Sunni negotiator, said. “The first of the three days is about to end and the situation is exactly as it was before.

“There is no seriousness about solving these issues. The Shias are manipulating this to let the draft go as it is and the Americans are doing nothing to stop them.

“If there was any seriousness to solving this, we would have been in continuous meetings to reach a compromise, but what’s happening is they are doing exactly what they did for the last two weeks, which means there will never be a solution.”

There was little prospect of the warring sides sitting down together soon. Mr Hamoudi even questioned the legitimacy of his Sunni colleagues, saying that unlike the Shia and Kurd negotiators, they were appointed rather than elected, making the case for a referendum more compelling.

Sunnis hold 17 of 275 seats because of the Sunnis’ widespread boycott of the parliamentary elections, now seen as a huge political blunder.

“Those who are representing the brother Sunni Arabs are not elected,” Mr Hamoudi said. “Therefore, who can say that they really represent the people on the street? The Sunnis have to express their opinion.”

But relying on a referendum could prove to be a big gamble. Sunni public opinion appears even more staunchly opposed to the federal constitution than that of the negotiators.

In a referendum the constitution can be torpedoed if two thirds of voters in three provinces vote against it. Sunnis hold that majority in at least two provinces and possibly in a third. Recent days have seen a rush of Sunnis to register to vote in the referendum, most of them vowing to reject it.

Last night’s developments, and the marginalisation of the Sunni negotiators, brought a fresh stream to registration offices in Sunni triangle towns such as Fallujah and Samarra.

“We came here to register and we should not commit a mistake as we did before,” Hameed Hassan, one of those registering, said. In Ad Dawr, close to Tikrit, Saddam’s home town, hundreds of Sunnis demonstrated against the proposed draft constitution. “Long live the honourable insurgency,” they yelled.

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