Militants belonging to the Islamic State of Iraq and Levant (ISIL) have overpowered Baghdad's army and seized the northern part last week, posing a serious threat to the country's unity and raising chances of unleashing an all-out sectarian warfare.
US Secy of State John Kerry said Washington is ready for anything "constructive"
The militants also have the support of other armed Sunni groups who have raised questions about the regime of Prime Minister Nuri al-Maliki, a Shi'ite, accusing his regime of oppression. The ISIL and its allied forces have been counter-accused of committing war crimes by executing several non-combatant men in the country in the past few days.
The threat has made the US and Iran come together, a development unprecedented since the 1979 revolution in the Shi'ite power, and US Secretary of State John Kerry said that Washington would try all constructive means to fight the danger. He termed the threat to Iraq an "existentialist" one.
Sources in the Pentagon, however, said that the USA had no plans to coordinate military action with Iran.