BAGHDAD: The U.N. Security Council on Friday unanimously adopted a resolution aimed at weakening Islamists in Iraq amid reports of ISIS killing dozens of residents in besieged ethnic Yezidi areas.
Western media reported dozens of men from the Yezidi faith were massacred in the village of Kocho, 45 kilometers from the Kurdish-held town of Sinjar.
Some reports spoke of residents being told to convert to Islam or face summary execution.
While details of the latest incident were not immediately confirmed, such attacks in the past have led the U.S. military to take action.
U.S. President Barack Obama said a first week of airstrikes had broken the siege of the northern Sinjar mountain where civilians had been hiding from jihadists for more than 10 days.
The U.S. carried out more airstrikes Friday, the military said, after receiving reports that Islamic State of Iraq and Greater Syria (ISIS) “terrorists were attacking civilians" in the area.
As aid groups tried to cope with the hundreds of thousands of people displaced by Islamist advances in northern Iraq, ingredients of a fight-back began falling into place.
In New York, the U.N. Security Council passed a resolution aimed at weakening Islamists in Iraq and Syria by cutting off funding and the flow of foreign fighters.
And EU ministers agreed at an emergency meeting in Brussels to back the arming of Iraqi Kurdish fighters.
Iraqis and foreign powers meanwhile voiced relief after Prime Minister Nouri al-Maliki's decision Thursday to step down.
U.S. National Security Adviser Susan Rice said it was "another major step forward" in uniting Iraq, where ISIS jihadists have snapped up large swaths of land in a lightning and brutal offensive, raising the specter of genocide.
U.N. chief Ban Ki-moon also welcomed the divisive Maliki's move and called for the swift formation of "an inclusive, broad-based government ready to immediately tackle these pressing issues."
Support for Maliki's designated replacement, Haidar al-Abadi, has poured in from sources as diverse as Iran and Saudi Arabia.
When jihadist forces launched their offensive on June 9, Kurdish peshmerga forces initially fared better than retreating federal soldiers, but the abandoned U.S.-made weaponry government troops left in their wake turned ISIS into a formidable foe.
Jihadists advanced within miles of autonomous Iraqi Kurdistan last week, which was one of the factors that triggered US airstrikes and broad foreign support for the cash-strapped Kurds.
When the jihadists, who have controlled parts of Syria for months, swept across the Sunni heartland of Iraq in early June, they encountered little or no resistance.
Maliki's critics say he bears some of the responsibility for the crisis that brought the country to the brink of breakup for pushing sectarian policies that have marginalized and radicalized the Sunni Arab minority.
In another potentially game-changing development, 25 Sunni tribes in the western Anbar province, including some that had previously refused to work with a Maliki-led government, announced a coordinated effort to oust ISIS fighters.
"This popular revolution was agreed on with all the tribes that want to fight ISIS, which spilled our blood," Sheikh Abdul-Jabbar Abu Risha, one of the leaders of the fresh anti-jihadist drive, told AFP.
Anbar police chief Maj. Gen. Ahmad Saddak said security forces were backing the uprising, which began at 6 a.m. Friday.
"The battles are continuing until this moment," he said, putting the toll at 12 militants killed and adding: "We will not stop until the liberation of Anbar."
Anbar was the birthplace of a 2006 U.S.-backed uprising against extremist militants that helped bring about a sharp reduction in violence.
The decision by Maliki, 64, to turn the page on eight years in power was welcomed across much of Iraq, but some said little would change.
Maliki, who rose from anonymous exile to become a powerful and feared ruler, said late Thursday that he was stepping aside to "facilitate the progress of the political process and the formation of the new government.”