President Barack Obama said in an interview broadcast on Friday that the United States must tread cautiously in response to an apparent poison gas attack in Syria even as his aides debated over the options for possible military action against the Syrian government, Reuters reported. In his first public comments since Wednesday's attack in the Damascus suburbs, Obama called the incident "very troublesome" and a "big event of grave concern" but made clear he was in no rush to get war-weary Americans entangled in another Middle East conflict. Obama's wary response, which underscored a deep reluctance by Washington to intervene in Syria's 2-1/2-year-old civil war, came as senior U.S. officials weighed choices ranging from increased diplomatic pressure to the use of force, including possible air strikes on Syrian President Bashar al-Assad's forces, administration sources said. A high-level meeting including members of Obama's National Security Council, the Pentagon, State Department and intelligence agencies was held at the White House late on Thursday but made no decisions on what to recommend, officials said, and further discussions were planned. "What we've seen indicates that this is clearly a big event, of grave concern," Obama said in an interview on CNN's "New Day" program that aired as Assad's opponents braved the front lines around Damascus to try to deliver tissue samples to U.N. inspectors from victims of Wednesday's apparent poisoning. But when pressed about his comment a year ago that chemical weapons use in Syria would be a "red line," Obama - who was on a two-day bus tour of the Northeast - expressed caution. "If the U.S. goes in and attacks another country without a U.N. mandate and without clear evidence that can be presented, then there are questions in terms of whether international law supports it, do we have the coalition to make it work, and, you know, those are considerations that we have to take into account," Obama said. "The notion that the U.S. can somehow solve what is a sectarian complex problem inside of Syria sometimes is overstated," he said. -- SPA 18:23 LOCAL TIME 15:23 GMT تغريد