President Obama says the reported chemical attack in Syria this week is "clearly a big event of grave concern," but that the United States needs to carefully "think through" its response.
"When you start seeing chemical weapons used on a large scale; and again, we're still gathering information about this particular event, but it is very troublesome," Obama told CNN in his first public comments since Wednesday's reported attack.
Reports of a large-scale, chemical weapons attack by the government of Bashar al-Assad cited mass casualties that ranged from 1,000 to as many as 1,800 Syrian civilian deaths. Syria has denied gassing its own people.
The incident has challenged, once again, the president's "red line" in Syria, putting increased pressure on his administration to escalate its involvement in the crisis.
Defending his cautious response, the president told CNN's Chris Cuomo that the United States needs to "think through strategically" its reaction and assess "what is in our long-term national interests."
"Sometimes, what we've seen is that folks will call for immediate action, jumping into stuff, that does not turn out well, gets us mired in very difficult situations, can result in us being drawn into very expensive, difficult, costly interventions that actually breed more resentment in the region," he said, an apparent reference to the Iraq war.
Obama said the notion that the United Sates can solve "what is a sectarian, complex problem" inside Syria is "sometimes overstated."
"We've still got a war going on in Afghanistan," he noted. "I'm reminded that there are costs and we have to take those into account as we try to work within an international framework to do everything we can to see Assad ousted."
Obama said his administration is "gathering information about this particular event," and repeated calls for a U.N. investigation.
"We're moving through the U.N. to try to prompt better action from them and we've called on the Syrian government to allow an investigation of the site because U.N. investigators are on the ground right now," he said, adding that "we don't expect cooperation, given their past history."
The Obama administration is also evaluating whether to cut off aid to Egypt in response to the interim government's violent crackdown against supporters of ousted president Mohamed Morsi.
"We have to be very careful about being seen as aiding and abetting actions that we think run contrary to our values and our ideals," the president said. "So what we're doing right now is doing a full evaluation of the U.S.-Egyptian relationship.
"Ultimately, what we want is a good outcome there. But there's no doubt that, at this point, we've got to take a look and see what's in the long-term interests of the Egyptian people? What's in the long-term interests of the United States."