Bridging deep divisions between Sunni, Shia and Kurdish representatives over the proposed charter could help assuage rising sectarian tensions in the country, as grieving Shia continued to mourn relatives lost in the tragedy.
"There are some contacts, with the focal point of discussions revolving around the identity of Iraq," said top Shia negotiator Jawad al-Maliki, referring to Sunni demands that the whole country be declared part of the Arab world.
The Congress of the People of Iraq on Saturday called for amendment of the new draft constitution to be affirm the Arab identity of the country and rejected the "division of Iraq and squandering of its wealth and resources under the pretext of federalism”. The group, in a statement, urged the principle of decentralization as a temporary alternative to federalism.
In deference to Kurish sensitivities, the current text refers only to Iraq's Arab population as part of the Arab world, a clause that has angered the Arab League, of which Iraq was a founding member.
The statement also stressed what it called resistance to occupation through the use of all means as a legitimate right.
A cleric (R) supervises aid
distribution for stampede victims
A Western official confirmed that talks were taking place over possible changes to the draft charter, due to be put to a nationwide referendum on 15 October.
"There's a clear understanding that talks are going on," the official said on condition of anonymity.
"We have heard there is a group of Sunni negotiators advancing possible language they're hoping will be considered."
Sunnis opposed several aspects of the draft charter, particularly the establishment of a fully federal system with the possibility of autonomous regions in Arab as well Kurdish areas.
Almost all of Iraq's oil reserves are in the Kurdish north or Shia south, and Sunnis fear they could lose out in the distribution of revenues.
After Iraq's Shia and Kurdish-dominated parliament approved the draft, Sunnis started campaigning for a ‘no’ vote in October's referendum that could torpedo the text.
The rules for the ballot stipulate that the draft fails if it is defeated by a two-thirds majority in three provinces, and at least three are predominatly Sunni.
Sunni representatives confirmed they were in discussions with their Kurdish and Shia counterparts about a possible change of wording.
"There are some contacts and discussions about the amendment of certain points, including the unity of Iraq, the Arab identity of Iraq and the sharing of wealth," Sunni negotiator Saad Janabi told AFP.
"I think it will be possible to change the wording of some articles."
About 200 Sunni leaders, including representatives of the influential Association of Muslim Scholars, gathered in Baghdad on Saturday to press their demands.
The United Nations announced that it had distributed emergency funds to 200 Shia families that had lost loved ones in Wednesday's stampede.
The world body said there was an "urgent need" to help families cope, with counselling as well as tents and medical supplies.
Call for release
Iraqi political parties have demanded that US troops release the secretary general of the National Front for Liberation of Iraq. Abdul Jabbar al-Kubaisy was detained upon his return to Iraq about a year ago.