White House: "We Absolutely Agree" Paris Attacks Were an Act of War

A top Obama Administration official said the Paris attacks were an 'act of war.'

"Clearly all the signs point to this being the responsibility of ISIL," Rhodes said, using a name American officials often substitute for ISIS. "Certainly our information supports the strong likelihood that ISIL was involved in this."

French President François Hollande on Saturday blamed ISIS for the attacks, which he called "an act of war."

"And when faced with war, the country must take appropriate decisions," Hollande said. "An act committed by a terrorist army, DAESH [ISIS], against what we are, a free country that speaks together with the planet."

Rep. Adam Schiff, D-California, the ranking member on the House Intelligence Committee, said Sunday the Paris attacks marked the "failure" of the U.S.-led coalition campaign against ISIS in Syria and Iraq.

"The chief failure here is that we cannot allow ISIS to have this unmolested sanctuary in Syria and Iraq from which to plan and direct attacks against us," he said in an interview on "This Week."

The top Democrat on the intelligence panel, who has been briefed several times on the attacks since Friday, said the Paris plot was "likely directed and equipped out of Syria."

ABC's Benjamin Siegel contributed to this report.