By Waleed Ibrahim
BAGHDAD, May 8 (Reuters) - Members of a committee set up to reform Iraq's constitution said on Tuesday they hoped to submit recommendations to parliament next week, a major step towards meeting a political benchmark Washington has set for Baghdad.
The announcement comes amid growing U.S. impatience at Shi'ite Prime Minister Nuri al-Maliki's progress in implementing power-sharing agreements the United States says are key to reining in sectarian violence in Iraq.
Leaders from the Sunni Arab minority have in recent days renewed threats to quit Maliki's government because they believe Sunni concerns are not being addressed.
Dominant under Saddam Hussein -- ousted by the 2003 U.S.-led invasion -- Sunni Arabs saw the majority Shi'ites sweep to power in elections and have been demanding reforms as a condition for staying in government, including overhauling a constitution they fear will split Iraq into Sunni, Shi'ite and Kurdish federations to the disadvantage of Sunnis.
Washington, which says Sunni Arab participation in government is key to taming the Sunni-led insurgency, has stepped up pressure on Maliki to reach power-sharing agreements by September.
Under Iraq's first post-Saddam constitution, a committee charged with drafting constitutional reform proposals must submit its recommendations to parliament no later than four months after it began work.
The 31-seat committee, which includes Shi'ites, Sunni Arabs and ethnic Kurds, started work on Nov. 15, 2006. Because parliament recessed in January and February, the deadline falls on May 15, committee members said on Tuesday.
"May 15 is a deadline and we must deliver the reform drafts to the parliament by this date," Hasan al-Senaid, a committee member from the ruling Shi'ite Alliance, told Reuters.
"There are still some disputes between groups and they are all under discussion. We are trying to solve these disputes this week," Senaid said. Another committee member confirmed they hoped to submit the recommendations by next week.
Iraq's constitution was ratified in 2005. Shi'ites and Kurds voted overwhelmingly in favour while Sunni Arabs opposed it.
Among the most controversial articles are a law that allows provinces to win autonomy from Baghdad and form federal regions, the Arab identity of Iraq and rolling back a ban on former members of Saddam's Baath party from public office.
Sunnis fear federalism will allow ethnic Kurds in the north and Shi'ites in the south, where Iraq's oil reserves lie, to break away into their own states, sealing political doom for the Sunni Arabs.
Non-Arab Kurds, who were persecuted under Saddam's pan-Arab policies, have resisted wording on the Arab identity of Iraq.
Parliament, where Shi'ites have a majority, must approve any constitutional amendment by an absolute majority before a referendum takes place.
If rejected by a two-thirds majority in three of Iraq's 18 provinces, the constitutional amendment is automatically defeated, thus giving minority Kurds de facto veto power.