However, the president said the administration has confidence Assad was responsible for the most recent chemical attack on civilians and that he "must be held accountable":
PRESIDENT OBAMA: So what I've said is that we have not yet made a decision, but the international norm against the use of chemical weapons needs to be kept in place. And nobody disputes — or hardly anybody disputes that chemical weapons were used on a large scale in Syria against civilian populations.
We have looked at all the evidence, and we do not believe the opposition possessed nuclear weapons on — or chemical weapons of that sort. We do not believe that, given the delivery systems, using rockets, that the opposition could have carried out these attacks. We have concluded that the Syrian government in fact carried these out. And if that's so, then there need to be international consequences.
So we are consulting with our allies. We're consulting with the international community. And you know, I have no interest in any kind of open-ended conflict in Syria, but we do have to make sure that when countries break international norms on weapons like chemical weapons that could threaten us, that they are held accountable.
When you start talking about chemical weapons in a country that has the largest stockpile of chemical weapons in the world, where over time, their control over chemical weapons may erode, where they're allied to known terrorist organizations that, in the past, have targeted the United States, then there is a prospect, a possibility, in which chemical weapons that can have devastating effects could be directed at us. And we want to make sure that that does not happen.