(CNN) -- Jordan's King Abdullah II, one of the first Arab leaders to call for Syrian President Bashar al-Assad to step down, told CNN the attack on Wednesday that killed members of al-Assad's inner circle is a "tremendous blow to the regime."
But the king cautioned that he did not think the attack meant al-Assad's regime was about to crumble immediately.
The explosion, which a rebel leader said was detonated by remote control, killed Defense Minister Dawood Rajiha; Deputy Defense Minister Assef Shawkat -- al-Assad's brother-in-law; and Hasan Turkmani, al-Assad's security adviser and assistant vice president, the state TV reports said. Interior Minister Ibrahim al-Shaar was injured in the blast, state television said, adding that he "is in good health and that his condition is stable."
"This was a tremendous blow to the regime but again, Damascus has shown its resilience, so I think maybe we need to keep this in perspective," Abdullah told CNN's Wolf Blitzer. "Although this is a blow, I'm sure the regime will continue to show fortitude at least in the near future."
The king said the attack shows "cracks" in the regime, but his larger concern is the growing sectarian violence and whether it may lead to all-out civil war.
He said the danger of civil war is increasing, and it is al-Assad's last chance to try to stop that from happening.
"If it breaks down, if civil order breaks down to the point of no return, it will take years to fix Syria. I have a feeling we're seeing the signs of that. The only people that can bring us back from that brink is the president and the regime. This is the last chance they have."
The king said the international community is continuing to pursue all options involving a political transition, but that recent events made him concerned about whether they could work.
"I think, as we continue to pursue the political option, the realities on the ground may have overtaken us," he said. "Therefore I think the clock is ticking. I think we should continue to give politics its due, but if we haven't already passed that window, I think we're getting very close to a (civil war)."
Abdullah said he and other leaders are concerned about Syria's chemical weapons.
"One of the worst-case scenarios, as we are trying to look for political solutions, would be if some of those chemical stockpiles would fall into unfriendly hands," he said.
Jordan's leader said that the big concern is whether the weapons could fall into the hands of groups like al Qaeda, which he said he believes is operating in parts of Syria.
And he said not knowing who exactly is on which side complicates matters, including discussions of arming the rebels.
Blitzer asked the king whether he thought it would be acceptable for al-Assad to flee to another country or if he wanted him to be tried for war crimes.
"If Bashar leaving the scene and exiting Syria brings a stop to the violence and creates a political transition -- that's a lesser of evils," he said.
Abdullah said the international community must consider that, if al-Assad were to leave, questions would arise over who would replace him and how that might affect the restoration of order in Syria.
"It's not so much the individual, it's the system, and does the system allow for political transition?" Abdullah said. "And that's where I have my doubts."
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