U.N. Secretary-General Ban Ki-moon said on Monday he was deeply disappointed that a ceasefire in Syria had failed and he called on government troops and opposition groups to end the fighting immediately.
The ceasefire, proposed by international peace envoy Lakhdar Brahimi, was supposed to come into effect on Friday and last for the four days of the Muslim Eid al-Adha holiday.
But Syrian jets bombarded Sunni Muslim regions in Damascus and across the country on Sunday, activists said, as President Bashar al-Assad kept up air strikes against rebels despite the proposed truce.
On Monday, Syrian warplanes bombarded a rebel stronghold on the edge of Damascus, opposition activists said.
"I am deeply disappointed that the parties failed to respect the call to suspend fighting," Ban said in the South Korean capital, Seoul, where he accepted a peace prize. "This crisis cannot be solved with more weapons and bloodshed.
"I repeat my call for the Security Council, the regional countries and the region to support Joint Special Representative Lakhdar Brahimi's mission to help move forward on a political track," he said.