Obama: 'Grave concern' over alleged chemical weapons attack in Syria

President Obama on Wednesday described the possible use of chemical weapons in Syria as "a big event of grave concern" as advisors reportedly huddled at the White House to contemplate a military strike.

Obama did not suggest military action was imminent in his comments but said his administration was gathering additional information about the alleged attack, which rebel groups in Syria claimed killed more than 1,000 people outside Damascus.

"It is very troublesome," Obama told CNN in an interview.

He said rapidly deteriorating conditions in Syria appear to be "something that is going to require America's attention, and hopefully, the entire international community's attention."

"That starts getting to some core national interests that the United States has, both in terms of us making sure that weapons of mass destruction are not proliferating, as well as needing to protect our allies, our bases in the region," he said.

Senior officials from the State and Defense departments and the intelligence agencies met for three and a half hours at the White House on Thursday to weigh everything from a retaliatory strike to a sustained air campaign, The New York Times reported.

They left without having made a decision amid deep divisions on the wisdom of further intervening in the civil war that has been raging since March 2011.

Obama has come under increasing pressure to take action on Syria, both from some members of Congress — notably Sen. John McCain (R-Ariz.) — and U.S. allies like France.

Critics have noted that Obama threatened Syria's government with stark consequences if it used chemical weapons, a threat made just over a year ago.

Since then, there have been two claims that chemical weapons were used, but relatively little change in U.S. policy. After an initial report chemical weapons were used earlier this year, Obama allowed the transfer of light weapons to groups fighting the Syrian government.

The complicated web of rebel groups fighting Syrian President Bashar Assad's government also complicates the decision, as many are seen as having ties to extremist groups.

Gen. Martin Dempsey, the chairman of the Joint Chiefs of Staff, this week questioned whether it was in the U.S. interest to get involved in Syria. He noted that some rebel groups do not share U.S. interests.

Former Obama campaign adviser David Axelrod said Obama’s comments on the crisis in Syria are a signal that he will take action in the country’s civil war.

Axelrod said the president indicated during an interview with CNN on Friday that he recognizes the deteriorating conditions in the war-torn country.

“The use of weapons of mass destruction is a serious grave matter for the world.” Axelrod said Friday on MSNBC’s “Morning Joe.” “It’s a message to anyone who might use weapons of mass destruction, and that’s why [Obama] has to act here. I believe he will act.”

Tens of thousands of people have died already in clashes between rebels and supporters of Assad. The United States said earlier this year that Assad had already once used chemical weapons, provoking the White House to authorize the shipment of military aid to rebel forces there.

But the president said that the "notion the U.S. can solve a complex sectarian" situation in Syria was "overstated."

"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. Obama defended his Syrian policy, saying "the American people expect me to think through what we do." He also noted that the United States was "still spending tens of billions of dollars" waging a war in Afghanistan.

"Every time I sign a letter for a casualty of that war, 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.

Still, asked if it was safe to say that the U.S. was on a "more abbreviated timeframe" in terms of making a decision, Obama provided a one word answer: "Yes."

Julian Pecquet contributed.

This story was posted at 6:40 a.m. and updated at 11:41 a.m.