Jordanian King Abdullah II said Wednesday that he saw signs of Syria slipping into "a potential full-out civil war."

"I am seeing for the first time ... where we are getting to the level of the potential of full-out civil war," the king told CNN in an interview.

He was commenting on the suicide bombing attack on Syria's intelligence headquarters in the capital city of Damascus earlier in the day, in which Syrian Defense Minister Dawood Rajha and his deputy Assef Shawkat were killed.

The attack, which followed three days of violent clashes in the capital between the Syrian government and rebel forces, was called a tipping point in Syria's 16-month crisis by some analysts.

"In other words, it's getting very, very messy, to a point where I think the worst-case scenario for all of us in the region is when you get full-out civil war, there is no coming back from the abyss," King Abdullah said.

Calling Syria a country "far more complicated" than Iraq and others in the region, the king warned that " if civil order breaks down to the point of no return, then it'll take years to fix Syria."

"And I have a feeling that we're seeing the signs of that over the past three weeks," he said, adding that "the only people that can bring us back from that brink is, obviously, the president (Bashar al-Assad) and the regime."

"And I believe this is the last chance that they have," he stated.

The 16-month conflict in Syria has aroused deep concern of the international community.

U.S. Defense Secretary Leon Panetta declared the situation in the Middle East country "spinning out of control."

Russian President Vladimir Putin agreed Wednesday in a phone call with U.S. President Barack Obama to work jointly to find a solution to the crisis in Syria. But the Kremlin stressed that differences remain.

Russia, one of the five permanent members of the UN Security Council, has vetoed two resolutions that hinted at sanctions against Syria.

China has repeatedly warned against outside intervention in the Syrian situation.