After six months of talks, the constitutional reform committee had been expected to present parliament with a final draft of their recommendations today.
Committee members said they would ask political leaders to deal with sensitive issues such as sharing Iraq's oil wealth more equitably and ending a ban on former members of Saddam Hussein's party members holding public office.
''We have agreed on some articles but there are sensitive issues which need an agreement among the political leaders,'' said Saleem al-Jubouri, a member of the Accordance Front, the biggest Sunni political bloc in parliament.
The changes are aimed at bringing Sunni Arabs, who make up the backbone of the insurgency, more firmly into the political process.
U.S. President George W. Bush, under pressure to show tangible progress in the four-year-old war, has pushed Iraqi leaders to agree power-sharing legislation.
Jubouri said Sunni Arab and Shi'ite members of the committee disagreed with a Kurdish demand to allow regions to distribute oil income rather than the central government.
Some lawmakers from the ruling Shi'ite community, which was oppressed during Saddam's rule, are virulently opposed to former Baathists taking up government jobs.
Non-Arab Kurds, also persecuted under Saddam's pan-Arab policies, resist wording on the Arab identity of Iraq.
Sunni Arabs fear federalism will allow Kurds in the north and Shi'ites in the south, where Iraq's oil reserves lie, to break away into their own states. Sunni Arabs live mostly in central and western Iraq, which is poor in oil.
Jubouri said that one area of disagreement was the status of the ethnically mixed city of Kirkuk which sits atop one of the world's richest oilfields.
The current constitution says Iraq should hold a referendum on the final status of Kirkuk this year. While Kurds claim Kirkuk as part of Kurdistan, Arabs oppose this.
Another official in the committee said Arab members -- Shi'ites and Sunnis -- proposed making Kirkuk a separate region and dropping the idea of the referendum, which Kurds would anyway be likely to win.
''Of course the Kurds don't want this because they still want it to be part of their autonomous region,'' the official said.
''Only political leaders can decide on this. These are very sensitive issues.'' REUTERS SS VC2003