ISIL fighters seize large part of Iraq’s biggest oil refinery

Sunni fighters battled their way into Iraq’s largest oil refinery on Wednesday, a development that came as Iran raised the prospect of intervening in its neighbor’s spiraling internecine violence by vowing to defend all Shia holy sites.

Armed groups headed by the Islamic State of Iraq and the Levant (ISIL) were said to be in control of three-quarters of the Beiji refinery north of Baghdad. The oil fields represent the biggest source of fuel for domestic consumption in Iraq, and any outright seizure by ISIL would give the armed group a firm grip on energy supply in the north, where the local population has complained of fuel shortages.

The latest offensive comes after almost a year of bombings and reprisals by both Sunni and Shia groups in Iraq, violence that has largely undone the fragile balance of power between Iraq’s major sectarian groups.

In a sign of deepening chaos and lawlessness in the country, 40 Indian construction workers have been kidnapped in Iraq's second-largest city, Mosul, which fell to Sunni insurgents last week, India's Foreign Ministry said Wednesday.

Iraqi officials said the identity, motivation and whereabouts of the kidnappers remain unknown — but ISIL has scooped up dozens of other workers who are foreign nationals in its campaign across northern Iraq, according to Reuters.

No ransom demand has been received, officials said. 

The recent deterioration of the situation in Iraq — which has seen ISIL take large swaths of the country — also threatens to drag the United States back into the fray of Iraq’s domestic affairs.

Washington has already announced that 275 troops will be sent into a country it left in 2011. And American airstrikes are being mulled as a way of countering the surge of ISIL. The BBC reported on Wednesday that Iraq had formally asked the U.S. for strikes.

"We have a request from the Iraqi government for air power," said Martin Dempsey, chairman of the Joint Chiefs of Staff.

Meanwhile, the disintegration of security in Iraq has also raised the prospect of the U.S. working in cooperation with its usual foe Iran to restore some semblance of functioning governance.

But the use of American military might to aid Baghdad, and especially the possibility of a temporary alignment with Iran, had some on Capitol Hill balking at the administration's internal discussions.

"I can just imagine what our friends in the region, our allies, would be thinking by reaching out to Iran at a time when they continue to pay for terrorism and foster terrorism" in the region, said Republican Speaker of the House John Boehner.

On Wednesday, Iran's President Hassan Rouhani made the clearest declaration yet that Tehran was prepared to mobilize to stabilize its neighbor and make holy sites safe.

"Regarding the holy Shia shrines in Karbala, Najaf, Kadhimiya and Samarra, we announce to the killers and terrorists that the big Iranian nation will not hesitate to protect holy shrines," he said.

Rouhani said many people had signed up to go to Iraq to fight, although he also emphasized that Iraqis were prepared to defend themselves: "Thanks be to God, I’ll tell the dear people of Iran that veterans and various forces — Sunnis, Shias and Kurds all over Iraq — are ready for sacrifice."

Millions of Shia pilgrims visit Iraq's holy sites each year. Iraqi government forces are holding out against Sunni fighters in the city of Samarra north of Baghdad, site of one of the most important Shia shrines. Meanwhile, Sunni fighters have vowed to carry their offensive south to Najaf and Karbala, seats of Shia Islam since the Middle Ages.

Shias represent about 60 percent of Iraq's 32 million people, with Sunnis and smaller minority groups comprising the other 40 percent.

Iraq’s Prime Minister Nouri al-Maliki has called for national unity to counter the ISIL advance, urging his country's influential Sunni tribes to renounce the fighters. The cooperation of those tribes was key to securing the truce that helped end Iraq’s raging sectarian war in 2007.

"I call upon the tribes to renounce those who are killers and criminals who represent foreign agendas," he said in a televised speech on Wednesday.

Maliki also hosted a national unity summit late Tuesday. The meeting included prominent Sunni members of Iraq’s parliament, but it was not clear if the summit resulted in any firm resolution.

After the closed-door meeting, Ibrahim al-Jaafari, a Shia politician who held the post of prime minister before Maliki, read a statement.

"No terrorist powers represent any sect or religion," Jaafari said, while issuing a vague promise of "reviewing the previous course" of Iraqi politics.

Afterward, most of the leaders, including Maliki and Usama al-Nujaifi, the leading Sunni present, walked away from each other in silence.

The meeting comes amid pressure from the U.S., among others, for Maliki to do more to address perceived political exclusion among Sunnis, the minority that ran Iraq until Saddam Hussein was deposed from power following the 2003 invasion.

Al Jazeera and wire services