Iraq's Shiite-dominated constitution committee will submit an amended draft charter to parliament this weekend despite opposition from minority Sunni Arabs who rejected a proposed compromise, negotiators said Saturday.

The chairman of the committee, Sheik Humam Hammoudi (search), a Shiite, said "there has been an agreement on the differences including the federalism issue. This will give guarantees for the Sunnis."

But Sunni negotiators said they did not accept the revised document, and one of them, Saleh al-Mutlaq, called on Iraqis to reject the document in the Oct. 15 referendum, warning of a "terrifying and dark future awaiting Iraq."

Hammoudi said 5 million copies of the final version would be printed in Arabic and Kurdish — which the new charter designates as official languages — and distributed to the public along with their monthly food rations.

The development was a blow to President Bush's efforts to rally support for a deal. He telephoned a top Shiite leader, Abdul-Aziz al-Hakim, and urged the Shiites to make compromises with the Sunnis in the interest of national unity. A process designed to bring Iraq's disparate communities together appeared to be tearing them apart.

Despite more than two months of talks, the process bogged down because the various factions could not agree on fundamental issues involving the future of Iraq. These included the country's identity, whether Iraq would continue as a centralized state or a federation based on religion and ethnicity and whether former members of Saddam Hussein's Baath party (search), most of them Sunnis, would have a future in the new Iraq.

The issue of federalism is critical: Sunnis fear not only a giant Shiite state in the south but also future bids by the Kurds to expand their region into northern oil-producing areas, as they have demanded. That would leave the Sunnis cut off from Iraq's oil wealth in the north and south. More than a million Sunni Arabs live in areas dominated by Shiites.

Thousands demonstrated in support of radical Shiite cleric Muqtada al-Sadr (search) in a half-dozen cities, and there were clashes with rival Shiites in the holy city of Karbala, part of ongoing friction that erupted among Shiites during the constitution crisis. Some pro-Sadr protesters raised the issue of the constitution but most focused on demands for improved services.

Al-Mutlaq, the Sunni negotiator, told Al-Jazeera television of the breakdown in the talks after Sunnis studied compromise proposals offered by the Shiites on federalism and purges of former Baath Party members. The Sunnis had asked that decisions on both issues be delayed until a new parliament is elected in December, but the Shiite offer was insufficient to satisfy Sunni demands.

"There is a terrifying and dark future awaiting Iraq," he said. "It is important to present services for the Iraqis now, as well as to maintain security, and it is not important to write a piece of paper that all Iraqis disagree on."

Asked about Shiite offers, he replied: "We are still far from what we need and what the people need."

"This is the end of the road," government spokesman Laith Kubba told Al-Arabiya television. "In the end, we will put this constitution to the people to decide."

Kubba, a Shiite, told Al-Arabiya that the conflict was between rival visions for Iraq.

"One group sees Iraq as one sovereign state while another sees a country made up of two or three parts," he said. "An agreement between all parties is an illusion and a consensus is impossible. Therefore, the draft must be put for the people" to decide.

The Shiite alliance and the Kurds together control 221 of the 275 parliament seats and could win easily in a parliamentary vote on the charter, which requires only a majority. And with 60 percent of the population, the Shiites and their Kurdish allies are gambling that the draft would win approval in the referendum.

However, the perception that the Shiites and Kurds pushed through a document unacceptable to the Sunnis could sharpen religious and ethnic tensions.

Al-Mutlaq's statements came after Parliament speaker Hajim al-Hassani canceled a planned news conference expected before midnight Friday and instructed a television crew to shut down for the night.

At stake is a political process that the United States hopes will in time curb the Sunni-dominated insurgency, and along with a better-trained and equipped Iraqi security force, enable the Americans and their international partners to begin bringing home their troops next year.

With more than 1,800 U.S. deaths since the war began in 2003 and falling poll numbers, the White House needs to show something positive from Iraq to counter the depressing litany of car bombings, assassinations and American battle deaths.

Unlike their Shiite and Kurdish partners, the Sunni Arab delegates in the talks on the constitution are not elected officials but were appointed by community leaders and may lack negotiating room. Some Sunni clerics also have condemned as anti-Islamic parts of the document their own negotiators have tacitly accepted.

Sadoun Zubaydi, a Sunni member of the drafting committee, blamed the Americans for interfering in what was supposed to be an Iraqi process.

"To the last minute, this supposedly Iraqi process is being dictated by the U.S. government," he said.

Sunnis had insisted that the contentious issues of federalism and the fate of Baath party members be deferred to the next parliament, in which they hope to have more members. Sunni Arabs form an estimated 20 percent of the 27 million population but won only 17 of the 275 parliament seats because so many Sunnis boycotted the Jan. 30 election.

Sunni Arabs resent attempts to ban former Baath Party members from government posts or political life, feeling that would deprive them of livelihood in the new Iraq and prevent the country from using the talents of thousands of professors, senior executives and others who joined the organization to advance their careers.

However, Shiites suffered under Saddam, and hatred for his Baath party runs deep. A move by former Prime Minister Ayad Allawi (search), a secular Shiite, to quietly reinstate some former Baath members in the security services cost him considerable Shiite support, and his party fared poorly in the election.

Al-Mutlaq, the Sunni negotiator, said the Shiites told the Sunnis they would agree to remove the phrase "Baath Party" from the draft "but today they came again and put it in the draft in a very stupid way by removing the word `party' and keeping the word `Baath."'

He called on the Iraqi people to reject the constitution "because this constitution is the beginning of the division of the country and the beginning of creating disturbance in the country."

The constitution provides for a federal state, one in which provinces would have significant powers in contrast to Saddam's regime in which Sunnis dominated a strong central government.

The charter will allow any number of provinces to combine and form a federal state with broader powers. The Sunnis have demanded a limit of three provinces, the number the Kurds have in their self-ruled region in the north. The Sunnis have publicly accepted the continued existence of the Kurdish regional administration but within its current boundaries.

"Don't follow constitutions of the infidels," influential Sunni cleric Sheik Mahmoud al-Sumaidaei told the congregation Friday at Baghdad's Umm al-Qura mosque. "We don't want a constitution that brings the curse of separation and division to this country."