"This is not about al-Maliki," Xinhua quoted the top American envoy as saying in NBC's Today programme. "Let me stress, what the United States is doing is about Iraq. And nothing that the president decides to do is going to be focused specifically on Prime Minister al-Maliki."
There is a growing chorus of calls in Washington for Maliki to step down and pave the way for reconciliation among the country's dividing sects, though the White House has not publicly endorsed the idea.
Asked about slow US response to the lightning advances by the Islamic State in Iraq and the Levant (ISIL), whose fighters are pressing on to the capital city of Baghdad after seizing two major cities in northern Iraq -- Mosul and Tikrit -- in recent days, Kerry said: "Not the least of which is we didn't have operational capacity at that point in time, partly because Prime Minister Maliki denied the kind of permissions necessary."
The US moved its aircraft carrier USS George HW Bush from the North Arabian Sea into the Gulf days ago.
There is a growing chorus of calls in Washington for Maliki to step down
Kerry said the US is "deeply concerned" regarding the advances by the ISIL, an offshoot of Al Qaeda. "They represent a threat to every country in the region," he said. "They are more extreme even than Al Qaeda, and they are threatening the United States and western interests."
The White House said Obama has put all options on the table, except for sending back US troops into combat in Iraq, including airstrikes as requested by Maliki.
The Pentagon has planned to send Special Forces to Iraq, with focus on intelligence gathering, according to a CNN report.