"The president has been clear, the secretary has been clear, that the use of chemical weapons is absolutely unacceptable," U.S. State Department Spokesperson Jennifer Psaki told CNN's Hala Gorani on Wednesday.
It now seems as though that red line in the Syrian conflict may have been crossed, again, this time outside the capital, Damascus.
Psaki said the U.S. was calling for "unfettered" access for an investigative team to look into the incident, but also said that she did not "want to look into a crystal ball" and predict what the U.S.'s response might be should the use of chemical weapons be confirmed.
"We’ve been clear that boots on the ground is not part of the options being considered, but all options remain on the table," Psaki said. "I'm not going to outline those here."
Click above to watch Gorani's full interview with Psaki.