Iraq has asked the US for air support in countering Sunni rebels, the top US general said on Wednesday, after the militants seized major cities in a lightning advance that has routed the Shi'ite-led government's army.
But General Martin Dempsey, the chairman of the US military Joint Chiefs of Staff, gave no direct reply when asked at a congressional hearing whether Washington would agree to the request.
Baghdad said it wanted US air-strikes as the insurgents, led by fighters from the Islamic State of Iraq and the Levant, or ISIL, battled their way into the biggest oil refinery in Iraq and the president of neighbouring Iran raised the prospect of intervening in a sectarian war that threatens to sweep across Middle East frontiers.
"We have a request from the Iraqi government for air power," Dempsey told a Senate hearing in Washington. Asked whether the US should honour that request, he said: "It is in our national security interest to counter ISIL wherever we find them."
US officials, speaking on condition of anonymity, said the Iraqi request had included drone strikes and increased surveillance by US drones, which have been flying over Iraq for some time.
In the Saudi city of Jeddah, Iraqi Foreign Minister Hoshyar Zebari said Baghdad had asked for air-strikes "to break the morale" of ISIL.
While Iraq's ally, Shi'ite Muslim power Iran, had so far not intervened to help the Baghdad government, "everything is possible", he told reporters after a meeting of Arab foreign ministers.
US President Barack Obama briefed congressional leaders on Wednesday on efforts to get Iraqi leaders to "set aside sectarian agendas," reviewed options for "increased security assistance" and sought their views, the White House said.
A senior administration official said afterwards that Obama did not lay out a course of action at the meeting and had yet to make a final decision.
But a US national security source said the administration had quietly started consulting Congress about a plan for redirecting some current intelligence funding to help finance expanded US operations in Iraq.
Obama is facing pressure from US lawmakers to persuade Iraqi Prime Minister Nuri al-Maliki to step down over what they see as failed leadership in the face of the insurgency threatening his country.