Highlights 

• The situation in Iraq continues to deteriorate since bloody clashes broke out earlier this month.

• The insurgent groups, spearheaded by militants from the ISIL, come from the country's Sunni Arab minority.

• The crisis in Iraq has raised alarm in the U.S. and Iran, both of whom support the al-Maliki government.

BAGHDAD/WASHINGTON, June 17  -- The situation in Iraq continues to deteriorate since bloody clashes between insurgent groups and government forces broke out earlier this month.

Large swathes of Iraq's northern territories are now in the hands of militant groups, fuelling fears the country may split and a full-blown sectarian war erupt in the Middle East.

SECTARIAN RIFT

The insurgent groups, spearheaded by militants from the Islamic State of Iraq and the Levant (ISIL), come from the country's Sunni Arab minority. They believe the current Shiite-dominated government has treated Sunnis unfairly.

Shiite Prime Minister Nouri al-Maliki, meanwhile, denounced the insurgents as "terrorists" and has vowed to overcome them.

However, the government's troops have been dramatically defeated during the past week, with large parts of the country's north falling into the hands of the rebels.

On Monday, the insurgents seized the strategic city of Tal Afar near the Syrian border, and an Iraqi army helicopter was shot down during clashes.

The militants had previously seized Mosul, the second largest city in Iraq.

"Tal Afar has fallen into the hands of the militants of the ISIL, after they heavily pounded the city with mortar rounds and rockets since last night," said Mohammed Abdul Qader, head of the city council.

"The defenders of the city have withdrawn after running out of ammunition," he said, adding many of the officers disappeared after the battle.

Qader told Xinhua dozens of families had left their homes as a result of the street battles and mortar shelling. Most of the displaced families have fled to the city of Sinjar, some 60 km west of Tal Afar.

U.S, IRAN STEP IN

The crisis in Iraq has raised alarm in the United States and Iran, both of whom support the al-Maliki government.

The two long-time foes even discussed ways to stop the violence Monday on the sidelines of separate nuclear negotiations in Vienna, Austria.

Although the United States dismissed speculation of U.S.-Iranian military cooperation, Secretary of State John Kerry said the U.S. was "open to any constructive process."

State Department spokeswoman Jen Psaki said any discussion with Iran would concern ways Iran could help press al-Maliki's government to be more inclusive and treat all of Iraq's religious and ethnic groups equally.

Any talks with Iran "would be to discuss the political component here and our interest in encouraging Iraqi leaders to act in a responsible, nonsectarian way," she told reporters. "Certainly a discussion of that is something that we would be open to."

Meanwhile, the White House on Sunday began its deployment of up to 275 U.S. soldiers in Baghdad "to provide support and security for U.S. personnel and the U.S. Embassy in Baghdad," according to U.S. President Barack Obama.

While the force was being deployed for the purpose of protecting U.S. citizens and property, the personnel were still equipped for combat, Obama said in a report to Congress.

"This force will remain in Iraq until the security situation becomes such that it is no longer needed," he said

The Obama administration said it was mulling a range of options in support of Baghdad, including air strikes as requested by the Iraqi government, but would not send in U.S. ground troops.

While the White House continues to review its options, Iran's military leaders are already taking action.

The commander of Iran's elite Quds Force, Gen. Ghasem Soleimani, consulted with the Iraqi government Monday on how to halt the insurgents' advance.

According to media reports, Soleimani has been inspecting Iraqi defenses and reviewing plans with top commanders and Iranian-backed Iraqi Shiite militia.

INTERNATIONAL RESPONSE

UN Secretary-General Ban Ki-moon has condemned the recent upsurge of violence in Iraq.

A statement issued by Ban's spokesperson Sunday night said reports of mass summary executions by ISIL were deeply disturbing and underscored the urgency of bringing the perpetrators of such crimes to justice.

Saudi Arabia said Monday it rejected any foreign intervention in Iraq's domestic affairs as the country was trying to turn around a worsening security situation.

The Sunni-dominated country blamed Baghdad's "sectarian and exclusionary policies" for fuelling the insurgency.

Neighboring Turkey is sending humanitarian aid to the violence-hit cities of Iraq, particularly to the Turkmen-populated areas, while Jordan is closely following the situation and its army is on alert to protect the country from any spillover effects.

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