As a gunbattle raged south of Baghdad, US Senators. John McCain and Russell Feingold told Iraqi leaders Saturday that American patience was growing thin and they needed to urgently overcome their stalemate and form a national unity government.

In this hand out photo released by US army, US Sen. John McCain, R-Arizona talks to a US army soldier, in Baghdad, Iraq, Saturday, March 25, 2006. [AP]

It was the second high-level US delegation in less than a week delivering the same stark message to Iraqi politicians as the Bush administration steps up pressure to overcome the political impasse that threatens to scuttle hopes to start an American troop pullout this summer.

"We need very badly to form this unity government as soon as possible," McCain, R-Ariz., said at a news conference after meetings with President Jalal Talabani and Prime Minister Ibrahim al-Jaafari. "We all know the polls show declining support among the American people."

The US delegation also voiced alarm about increasing sectarian violence in Iraq showing itself in the daily count of drive-by shootings, bombings and dumped corpses, victims of execution-style killings in the shadowy Shiite-Sunni settling of scores.

Seven people ¡ª most civilians killed in their homes by mortar fire ¡ª died and several others were wounded in a gunbattle between forces of the Shiite Mahdi Army militia and Sunni insurgents near Mahmoudiya, about 20 miles south of the capital.

At least 13 other people were killed in scattered violence Saturday and two more bodies were found dumped in the capital, shot in the head with their hands and feet bound.

US Ambassador Zalmay Khalilzad, who has patiently shepherded negotiations to form a new government, already was looking beyond that task to the need to cap the sectarian, militia-inspired killing.

"More Iraqis are dying today from the militia violence than from the terrorists," Khalilzad told reporters during a visit to a sports complex refurbished with American aid. "This will be a challenge for the new government ¡ª what to do about the militias."

The country's leadership must "overcome the strife that threatens to rip apart Iraq," he said.

Nevertheless, a sixth session of multi-party meetings Saturday failed to overcome the logjam that has snarled formation of a government for more than three months.

Feingold, of Wisconsin and the ranking Democrat in the US delegation joined McCain in pressing for the quick formation of a government, but he spoke bluntly of his concern that the continued presence of American forces was prolonging the conflict.

"It's the reality of a situation like this that when you have a large troop presence that it has the tendency to fuel the insurgency because they can make the incorrect and unfair claim that somehow the United States is here to occupy this country, which of course is not true," Feingold said.

With November's midterm congressional elections drawing nearer and American voters increasingly disenchanted with the Iraq war, the two visits in quick succession by high-powered US politicians signaled deep concern over potential fallout from a lack of progress in Iraq.

"We are very concerned about the sectarian violence that is happening out there and how that erodes not only the confidence of the Iraqi people in this process, but certainly also the confidence of the American people and their commitment to this effort," Sen. John Thune, R-S.D., said.

Talabani, a Kurd, has formed a coalition with Sunni and secular politicians against a second term for al-Jaafari, a move that only deepened the government stalemate more than three months after the Dec. 15 parliamentary elections.

The US politicians met separately with each of the men, as well as the US commander in Iraq, Gen. George Casey.

On Tuesday, a delegation led by Sen. John Warner, the Virginia Republican who is chairman of the Armed Services Committee, delivered the same tough message, saying the uneasiness back home could force US lawmakers to press for a reduction in American troop strength if the government delay were prolonged ¡ª regardless of the consequences.

McCain agreed that the damage could be enormous.

Failure in Iraq, he said, would leave "this part of the world in chaos. Not just Iraq, but all of the surrounding countries as well."

In other violence Saturday, according to police:

** A female teacher was killed by Iraqi soldiers as she drove past their convoy in Baghdad.

** A Sunni mosque preacher was killed by gunmen when he stopped to have his car repaired in west Baghdad.

** Gunmen killed a man driving with his family and wounded his two sons in the capital.

** A bomb exploded in a traffic police hut near the Iraqi Finance Ministry in north Baghdad, killing four civilians and wounding five people, including a traffic policeman.

** Gunmen killed three people in the northern city of Mosul.

** A roadside bomb killed two people in Balabroz, 55 miles northeast of Baghdad.

** Drive-by gunmen killed the bodyguard of the head of Basra's Sunni Endowment, the organization that oversees the sect's religious property in the predominantly Shiite southern city.