Washington - President Barack Obama has not decided how to respond to rampant Sunni militants grabbing swathes of Iraq, but is looking at every option short of sending US combat soldiers back to war.
Officials said on Wednesday that Obama had not ruled out any possible courses of action, including air strikes against Islamic State of Iraq and the Levant (ISIL) fighters.
Signs also emerged of rising US pressure on Shiite Iraqi Prime Minister Nuri al-Maliki, who is being blamed in Washington for causing Iraq to splinter after discriminating against the minority Sunni community.
But there were no signs that renewed US military action was imminent in a war Obama had declared at an end in 2011, hoping to cement his political legacy.
"The only thing the president has ruled out is sending troops back into combat in Iraq, but he continues to consider other options," White House spokesperson Jay Carney said.
"Work is being done that will help us see with more clarity what the options available to the president are," Carney added, when asked to clarify whether Obama had ruled out air strikes.
Secretary of State John Kerry reinforced the message in an interview with NBC television.
"Nothing is off the table. All options are still available to the president," Kerry said, adding Obama was "very intensely vetting" his plan.
Obama's other options include a possible drone campaign against ISIL forces, which have seized Iraqi cities - including Tikrit and Mosul - or stepped up assistance and training to Iraqi government forces.Squandered gains
One official said that, while there was rampant speculation in Washington about US responses to the seizures of vast swathes of territory in Iraq by ISIL, Obama "has not made a decision."
Vice President Joe Biden, traveling in South America, drove home the US message that Maliki needs to lead all Iraqis, not just Shiites.
He told the Iraqi leader in a telephone call that he must govern in an "inclusive manner, promote stability and unity among Iraq's population, and address the legitimate needs of Iraq's diverse communities," a White House statement said.
Earlier, the top US military officer, General Martin Dempsey, blamed the Iraqi government for the deepening sectarian mire.
"There is very little that could have been done to overcome the degree to which the government of Iraq had failed its people," the chairman of the Joint Chiefs of Staff said.
"That's what has caused this problem," Dempsey told lawmakers when asked if the US could have taken action to counter the advance of Sunni militants.
A Wall Street Journal report said that Washington wanted Maliki out, believing that he would never preside over an inclusive Iraqi state.
US officials publicly say it is up to Iraqis to chose their leaders, but pledge to continually point out that governing in a non-sectarian way is a crucial qualification for office.
Earlier, Iraq had officially requested US air support against the rebels who have occupied some key cities during an eight-day offensive.
Obama met Democratic Congressional chiefs Senate Majority leader Harry Reid and House Minority Leader Nancy Pelosi and Republican party bosses, House Speaker John Boehner and Senate Minority Leader Mitch McConnell.
The meeting took place against revived and fierce political debate, with Republicans saying Obama had squandered the gains of a bloody war that was essentially won when he pulled out all US troops nearly three years ago.
Democrats charge that former president George W. Bush blew the lid off Iraq's bottled up sectarian stew by invading the country in 2003 and that Maliki threw away a chance for a stable future for Iraq wrought by US blood and treasure.
Before Boehner joined the talks, he asked for a "broader strategy for how we help keep the freedom that we paid dearly for the people of Iraq".Partisan clash
After the leaders emerged, McConnell underscored the partisan clash over Iraq.
"Unfortunately, Iraqi security forces are now less capable than when the president withdrew the entirety of our force without successfully negotiating a remaining US presence capable of preserving our gains and mentoring our partners," McConnell said.
Pelosi said she was pleased Obama would not send troops back to Iraq and argued Obama would not need new authorisation from Congress if he took military action in Iraq.
McConnell also later told reporters Obama believed he did not need new authorisation from lawmakers to act.
The row over what to do about the current crisis in Iraq also drew in a venerable combatant: former vice president Dick Cheney, who penned a savage critique of Obama's foreign policy on the Journal's opinion page.
"Rarely has a US president been so wrong about so much at the expense of so many," Cheney said in a column co-authored by daughter Liz Cheney, a former State Department official.