The speaker of the National Assembly announced to applause that the midnight deadline for the constitution had been met, but he dismissed the chamber without a vote saying there would be three more days of talks, Reuters reported.
While negotiators representing the majority Shiites, Kurds and Sunnis finished the draft constitution and submitted it to parliament with only minutes to spare, they immediately withdrew it over fierce opposition over issues such as federalism, which Sunnis are concerned will leave them out of most of the country's vast oil wealth.
The 15 Sunni Arab members of the drafting committee issued a statement early Tuesday saying they had rejected the constitution because the government and committee did not abide by an agreement for consensus.
"We reject the draft constitution that was submitted because we did not have an accord on it," said Sunni delegate Nasser al-Janabi, according to the Associated Press.
Speaker Hajim al-Hassani said four points, including the key issues of the concept of a "federal" state and control of oil revenues, were still in dispute, Reuters reported. The same issues caused the Iraqi representatives to extend the original Aug. 15 deadline by a week.
One Shiite negotiator cautioned it was "not possible to please everyone." But the Shiite chairman of the 71-member committee, Humam Hammoudi, said "many things have been achieved in this constitution and we hope it will be a real step toward stability," reported the AP.
On Sunday, Sunni representatives on the drafting committee urged the United States and United Nations to keep Shiites and Kurds from pushing a constitution through parliament without their consent, warning it would only worsen the crisis in Iraq.
Negotiators from three main communities, Shiites, Kurds and the minority Sunni Arabs, met in Baghdad's Green Zone for a new round of talks Monday.
The National Assembly must either accept or reject the constitution or the body will be dissolved. If the assembly approves the constitution, it must be put to a referendum by Oct. 15. If any three of Iraq's 18 provinces reject the referendum by two-thirds or more, the constitution will be rejected, according to Reuters.
If the referendum is ratified, elections will be held in December for a full-term parliament with full powers.