Iraq's scheduled January elections may be postponed by more than a month because of a dispute over an election law, officials said Wednesday, a delay that could threaten the planned U.S. withdrawal of combat troops.

Iraqi lawmakers have been working for months to pass a law needed to reform the election process, seeking to make it more representative of Iraq's ethnic and religious groups. It is unclear what a long delay would mean for the United States, which is scheduled to end combat missions in August.

Former Prime Minister Ayad Allawi, who heads a small bloc in parliament, said a preliminary proposal from various political factions calls for moving the election to Feb. 27, but it also could be further pushed to March 1.

Allawi told Al-Arabiya television that meetings are planned for Thursday to look at possible new dates for the parliament election, which is scheduled for Jan. 16.

Earlier, Sandra Mitchell, the head of the United Nations Assistance Mission for Iraq's electoral commission, suggested to parliament Speaker Ayad al-Samarie the election could possibly even be moved to March, the speaker said on his Web site.

Iraq's vice president has vetoed the law because he wanted more seats for Iraqis living abroad, most of whom are Sunnis. The minority party has seen its once-privileged status evaporate since the fall of Saddam Hussein.

President Barack Obama has ordered the withdrawal of all combat troops by Aug. 31, 2010, leaving up to 50,000 troops in advisory roles. Under an Iraqi-U.S. security agreement, those remaining troops would leave by the end of 2011.

For now, the top U.S. commander in Iraq has said the pullout remains on schedule.

Prime Minister Nouri al-Maliki, a Shiite, and President Jalal Talabani, a Kurd, held a joint press conference Wednesday to call on the elections law to be passed.

"I have met with al-Maliki and our point of view is identical over the passing of the elections law," Talabani said.

Al-Maliki said if the elections law failed, it would be "the destruction of all we built in the political process."

Both Sunnis and Kurds criticized earlier versions of the legislation. The parliament amended the law with a version that pleased the Kurds but not the Sunnis.

Despite the mounting pressure, Sunni Vice President Tariq al-Hashemi gave no signs of changing his position on vetoing the law if more parliamentary seats are not distributed.

"Time is running out and al-Hashemi is sticking to his position that he is not ready to give up the rights of the Iraqi people. The veto might be the last remaining option, if the current talks yield no results," said Abdul-Ilah Khazim, al-Hashemi's spokesman.

Though violence in Iraq has declined dramatically in recent years, Iraqi and U.S. military officials have expressed concern that a delay in the election could destabilize the hard won security gains.

On Wednesday, an American airstrike in northeast Iraq killed one gunman after a joint U.S.-Iraqi foot patrol was attacked. The airstrike was called in after five gunmen attacked the patrol as it was searching a building in the town of Sadiyah in the volatile Diyala province, the U.S. military said in a statement.

But a police official said the gunmen opened fire on the soldiers, believing they were insurgents. A year earlier, the same house had been attacked by insurgents, the official said.

The police official spoke on condition of anonymity because he was not authorized to release the information to the media. Sadiyah is 60 miles northeast of Baghdad.

Elsewhere, gunmen attacked a popular cafe in western Baghdad, killing one and wounding three, an Iraqi police official said. Gunmen also attacked an Iraqi army checkpoint in eastern Baghdad, killing one solider and wounding another, said another police official.

Both officials spoke on condition of anonymity because they were not authorized to release the information.