Annan: Syria could plunge into civil war

(CNN) -- Special envoy Kofi Annan told the U.N. Security Council on Tuesday that international observers are the last hope for success of a peace plan in Syria. Otherwise, he warned, Syria is sure to plunge into full-scale civil war.

"The implication of that is quite frightening," Annan told reporters after briefing the Security Council. "We cannot allow that to happen."

Annan plans to return to Damascus soon to seek adherence to a cease-fire. The killing, he said, must stop immediately.

"There has been some decrease in the military activities, but there are still serious violations in the cessation of violence that was agreed," Annan said. Read More