Speaking to reporters in Jerusalem, Kerry said the situation in Fallujah was an issue for the Iraqi government to handle, but vowed the United States would help.
"We are not contemplating putting boots on the ground," Kerry said. "This is their fight, but we're going to help them in their fight."
Kerry appeared to confirm that the U.S. strategy was to back the tribal militias that have locked horns with al-Qaida and the militant Islamic State of Iraq in Levant forces that were currently in control of Fallujah.
Kerry said the fall of Fallujah made the upcoming peace talks on Syria even more important. Militants from the Islamic State of Iraq have become a significant player in the Syrian revolt, but other rebel groups recently turned on them after they sought to impose harsh Islam-based rule over areas they occupy.
Kerry said the upcoming peace conference in Geneva, Switzerland, on Syria could be an important step toward snuffing out al-Qaida's influence in the entire Middle East.
"This is a fight that is bigger than just Iraq," Kerry said. "This is part of the reason why the Geneva conference is so critical, because the rise of these terrorists in the region and particularly in Syria, is part of what is unleashing this instability in the rest of the region."
Kerry said serious participation in the talks by Iran would be constructive and could even lead to a breakthrough on the standoff over its nuclear weapons program. But, he said, Geneva was not the place for grandstanding or stalling. "Iran knows exactly what it has to do with respect to the nuclear program as well as with respect to Geneva," Kerry said. "And it's very simple: Come join the community of nations and do what all of us are committed to doing, which is try to bring about a peaceful resolution in Syria."