The United States will help Iraq fight an al Qaeda-linked group that seized the city of Fallujah in the west of the country, but will not send American troops, Secretary of State John Kerry said on Sunday.

“We will stand with the government of Iraq and with others who will push back against their efforts to destabilize,” Kerry told journalists as he left Jerusalem for Jordan and Saudi Arabia. “We are going to do everything that is possible. I will not go into the details.”

The Islamic State in Iraq and Levant (ISIL), which took control of Fallujah and Ramadi over last week, is one of the strongest rebel groups in Syria and has imposed a strict version of Islamic law in territories it holds.

U.S. intelligence officials said Friday the situation in western Iraq was “extremely dire” after the radical forces raised their flag in the town of Fallujah — site of two of the bloodiest battles during the Iraq war — and gained control of the city.

Kerry admitted that the U.S. was “very, very concerned” by the fighting, and called ISIL “the most dangerous players in that region.”

The ISIL claimed responsibility for a suicide car bombing in in Lebanon on Saturday.

Reuters contributed to this report. 

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