Baghdad, Iraq ? Sunni Arab leaders showed no sign of compromise Tuesday as they prepared to resume talks in yet another bid by the Shiite-led government to win approval of Iraq’s new constitution.

The U.S. ambassador said every effort must be made to win Sunni agreement, but the chairman of the drafting committee doubted that differences could be resolved quickly and suggested parliament might submit the current draft to voters.

Failure to win over the once-dominant minority would undercut the U.S. strategy of using the constitution to lure Sunni Arabs from the Sunni-dominated insurgency so American and other foreign troops could start to go home.

Representatives of the major factions – Shiites, Kurds and Sunnis – scheduled negotiations for this morning in the heavily guarded Green Zone after Sunnis angrily rejected the draft presented to parliament Monday only minutes before the midnight deadline.

Sunni negotiators opposed several parts of the draft, including federalism, references to Saddam Hussein’s Sunni-led Baath Party and the description of Iraq as an Islamic – but not Arab – country. Parliament put off a vote on the document for three days to try to win over Sunnis.

On Tuesday, the country’s biggest Sunni political group repeated those complaints, adding that the decision by Shiites and Kurds to submit the draft to parliament over Sunni objections violated an agreement that no document would be considered final unless all parties agreed to it.

“The sticking points are related to the identity of Iraq, federalism, power-sharing and purifying the constitution of any mention of sectarianism,” said the Iraqi Islamic Party, which has roots in the fundamentalist Muslim Brotherhood.

“If the wording is not re-examined in a way that serves the interests of the country and ensures equality for everybody, then this draft is considered as rejected, as a whole and in details.”

Saleh al-Mutlaq, one of four principal Sunni negotiators, also complained on Al-Jazeera television that the draft was sent to parliament without consensus.

“This procedure was illegal,” he said.

With the Sunnis digging in their heels, the chairman of the 71-member committee that drafted the constitution said three days were not enough to resolve Sunni objections. He said the draft might have to be approved by the Shiite- and Kurdish-dominated parliament as is and taken to the people in a referendum Oct. 15.

Chairman Humam Hammoudi, a Shiite, noted that unlike Shiite and Kurdish negotiators, Sunni Arabs on the committee were not elected parliament members but were appointed to the panel. Sunni Arabs won only 17 of 275 parliament seats because many Sunni voters boycotted Jan. 30 elections.

“Those who are representing the brother Sunni Arabs are not elected,” Hammoudi said. “Therefore, who can say that they really represent the people on the street … therefore, the Sunnis have to express their opinion” in the referendum.