Kerry: This is a "vital moment" for Assad to work with opposition

As the Obama administration begins providing direct aid to the Syrian Opposition Coalition, now is a crucial moment for Syria's long-time dictator, President Bashar Assad, to decide whether he will engage with the international community, Secretary of State John Kerry said in an interview with CBS News today.

"This is a vital moment to try to get him to realize he either comes to the table to negotiate, or the opposition is going to get greater and greater support, and ultimately he will have to make that decision," Kerry told CBS News' Margaret Brennan in Doha, Qatar.

In his first official trip overseas as secretary of state, Kerry said that the "peaceful out" for Assad involved appointing someone to be part of a transitional government -- a solution the international community and the Syrian opposition has embraced.

That said, Kerry added, "What we've also made clear is we're not going to let up the effort to hold President Assad accountable for his random killing of Syrian citizens, for sending SCUDs to destroy hospitals, and shoot women and children in places where he knows they will be at the time they shoot. He is literally destroying his country in the effort to hold onto power."

The Syrian rebel commander receiving aid from the U.S. has said to CBS News that his fighters could take Damascus in a month if they're given missiles and tanks. Kerry explained, however, that President Obama is providing humanitarian and nonlethal aid "in order to try to seek a peaceful resolution and reduce the killing."

Kerry noted that other countries are helping the opposition as well, and that Mr. Obama has other options available.

"But right now, he and I think we feel that this step hopefully will send the right message," he said. "Our objective is to try to reduce the killing, not increase it; to hopefully avoid chaos, not guarantee it. And so measured steps are being taken in an effort to try to find the Russians and the Iranians and others to see this opportunity for a transitional government according to the Geneva process. But obviously, if that doesn't work, every other option is available."

Kerry declined to say whether he'll recommend for the U.S. to ratchet up aid, but he said the stepped up assistance has "already had some impact."

"I've noticed a lot of flurry of the foreign minister of Syria rushing to Tehran, other public comments," he said. "I think we need to proceed thoughtfully and carefully as the president has decided to."