The committee was due to submit their changes to parliament today. But committee members told the AP news agency that they will ask parliament for a weeklong extension instead.
Iraqi politicians say the main stumbling block is the future status of Kirkuk. Kurdish politicians want to annex the oil-rich city to their semiautonomous northern region, but Arabs and Turkomen object to that proposal
There is also disagreement over the powers of the prime minister, and over whether to describe Iraq as an Arab country, as the Sunnis want.
The parliamentary committee was set up four months ago to address Sunni Arab concerns over the constitution.
The pipeline from Kirkuk to Turkey is one of Iraq's main oil-export lifelines (epa file photo)
THE FUTURE OF THE ECONOMY. The uneven distribution of Iraq's oil resources has long been a source of tension among the country's ethnic and sectarian groups. Since the fall of Saddam Hussein, the tangled quest to find an equitable way to share oil revenues has been a major stumbling block on the road to national unity.