Jen Psaki told reporters chemical weapons use in Wednesday's attack has not been conclusively proved. Syrian rebels and human rights groups released photographs and video showing the apparent victims of a chemical attack and said hundreds of people were killed near Damascus early Wednesday.
A U.N. team is in Syria but has been unable to examine the site of the alleged attack, Psaki said.
Psaki responded to a question from a reporter who said French and Turkish leaders along with critics of Obama administration policy like Sen. John McCain have called for stronger action against the government of President Bashar Assad.
"Well, as I mentioned, we're still focused on nailing down the facts," Psaki said. "The intel community is focused on that. The administration is focused on that. If these reports are true, it would be an outrageous and flagrant escalation of the use of chemical weapons by the regime, so our focus is on nailing down the facts."
Psaki said the photos released Wednesday showed events that "shocked the consciousness, and anyone would see as beyond the pale." But she said it is still important to gather information before deciding on the next steps.