Doug Stanglin

USA TODAY

As Iraqi government leaders said that they feel "abandoned" by the international community, President Obama said Thursday that he is not sending troops to combat militia groups that are taking control of the country's cities.

Obama said he is tasking Secretary of State John Kerry to help find a diplomatic solution and will deploy up to 300 military advisers to provide more intelligence, surveillance and reconnaissance to help stop the encroaching militias.

Obama spoke as Sunni militants and government soldiers battle for control of Iraq's largest oil refinery. Both sides are claiming control of the Beiji oil facility about 150 miles north of Baghdad. A witness tells the Associated Press that militants have hung their black banners on watchtowers at the refinery, where a huge fire rages in one of its tanks.

Some workers say the militants had seized most of the facility and that troops were concentrated around the control room.

A top military security official in Baghdad, speaking on condition of anonymity, however, tells the AP that government troops protecting the refinery, the country's largest, are still inside the facility.

A military spokesman, who spoke on condition of anonymity, tells the AP that troops had repelled repeated attacks by the militants, led by the jihadist Islamic State in Iraq and the Levant (ISIL).

Forty insurgents were killed overnight and on Wednesday, he added, denying the facility was close to being overrun.

Nearly all the 15,000 workers at the refinery and 100 foreign experts left Tuesday when the plant was shut down in anticipation of the attack.

On Thursday morning, the remaining 250 to 300 workers were evacuated under an agreement brokered by local tribal leaders, one of the workers told the Reuters news agency.

The battle over Beiji, which supplies much of the country's domestic fuel, has sparked fears that Iraqis will soon experience long lines at petrol pumps and electricity shortages.

The latest clash comes as President Obama met Wednesday with top leaders of Congress to explore options in the conflict.

The fighting at Beiji also comes as Iraq has asked the U.S. to launch airstrikes targeting militants from ISIL. While Obama has not fully ruled out the possibility of launching airstrikes, such action is not imminent, officials said, in part because intelligence agencies have been unable to identify clear targets on the ground.

Gen. Martin Dempsey, the chairman of the U.S. Joint Chiefs of Staff, confirmed the U.S. had received a request for air power to stop the militants, but highlighted the uncertain political situation in Iraq.

"The entire enterprise is at risk as long as this political situation is in flux," he told a Senate panel Wednesday. He added that some Iraqi security forces had backed down when confronted by the militants because they had "simply lost faith" in the central government in Baghdad.

A spokesman for Prime Minister al-Maliki's Dawa party, Zuhair al-Nahar, said Thursday that the prime minister had met Sunni Arab and Kurdish leaders and that they had "come out in a united stand."

"My message from all the leaders in Iraq is that they feel abandoned, that they want America, Europe, the U.N., to take immediate action to rectify the military situation," he told the BBC.

The U.S. has pushed Iraq to present its people a clear coalition to fight the militants, with Vice President Joe Biden offering praise Wednesday for Iraq's Shiite, Sunni and Kurdish leaders as a means to tamper the sectarian anger roiling the country. It's unclear whether that will work, as al-Maliki's Shiite-led government has faced widespread dissatisfaction from the nation's sizable Sunni and Kurdish minorities.

Al-Maliki, a Shiite, has rejected charges of bias and instead said the crisis has led Iraqis to rediscover "national unity."

"I tell all the brothers there have been negative practices by members of the military, civilians and militiamen, but that is not what we should be discussing," al-Maliki said Wednesday. "Our effort should not be focused here and leave the larger objective of defeating" the militants.

The campaign by the al-Qaeda-inspired Islamic State militants has raised the specter of the sectarian warfare that nearly tore the country apart in 2006 and 2007, with the popular mobilization to fight the insurgents taking an increasingly sectarian slant, particularly after Iraq's top Shiite cleric made a call to arms on Friday.

The Islamic State has vowed to march to Baghdad and the Shiite holy cities of Karbala and Najaf, home to some of the sect's most revered shrines, in the worst threat to Iraq's stability since U.S. troops left in late 2011. The militants also have tried to capture Samarra, a city north of Baghdad and home to another major Shiite shrine.

In an incident that harkens back to the dark days of Iraq's sectarian bloodletting of 2006 and 2007, the bullet-riddled bodies of four men, presumably Sunnis, were discovered in the Shiite Baghdad district of Abu Dashir on Thursday, police and morgue officials said. The bodies were handcuffed and had gunshot wounds to the head and chest.

Also in Baghdad, a roadside bomb hit a police patrol on a highway in the east of the city, killing two police officers and wounding two, police and hospital officials said. Earlier Thursday, a car bomb exploded inside a parking lot in Baghdad's southeastern Shiite neighborhood of New Baghdad, killing three people and wounding seven, the officials said.

All officials spoke on condition of anonymity because they were not authorized to speak to the journalists.