United Nations-Arab League envoy Lakhdar Brahimi Sunday warned that the conflict was worsening in Syria and could "turn into a hell", but said a political solution was still possible, DPA reported.
"This political solution includes a ceasefire, the formation of a transition government with full powers and other steps leading to elections," he said in Cairo, apparently referring to agreements reached in Geneva in June at the Action Group for Syria meeting.
The veteran Algerian diplomat said that a delay in implementing the peaceful solution would risk turning Syria into a new Somalia and jeopardizing global security.
"The situation in Syria is very bad and worsening," he said after talks with the head of the Arab League Nabil al-Arabi.
"The pace of deterioration is increasing," he added, hoping that a solution could be reached before the second anniversary of the Syrian uprising in March.
"Syria has two possibilities: either a political solution fulfilling the legitimate aspirations of Syrian people or Syria could turn into a hell," Brahimi added.
The Syrian opposition has repeatedly said a political solution to end the country's 22-month conflict is impossible unless President Bashar al-Assad steps down.
More than 45,000 people have been killed in Syria since the conflict started in March last year, according to the opposition.
Brahimi met with al-Assad in Damascus earlier in the week, but did not share details of those talks.
The peace envoy also met with Russian Foreign Minister Sergey Lavrov in Moscow on Saturday.
Russia, a major ally of Syria, said that al-Assad was not planning to relinquish power.
In Syria itself, the rebel Free Syrian Army claimed to have captured the town of Rankus and government security checkpoints on the outskirts of the capital Damascus.
Fighting was meanwhile raging between al-Assad's troops and rebels in the towns of Harsta and Arabeen near Damascus, said the opposition Syrian Observatory for Human Rights.
The rebels have been fighting government troops in and around Damascus for weeks, raising the possibility that al-Assad could lose his hold on the capital.
At least eight civilians were killed Sunday when a shell struck a marketplace in the embattled northern city of Aleppo, according to the observatory.
Some 390 people were killed across Syria on Saturday, making it one of the bloodiest days in the country's conflict, said activists.
The majority of the deaths occurred in an alleged massacre in the district of Deir Balba in the restive central province of Homs.
Some activists claimed that around 200 people were executed in the district after government troops recaptured it from rebels.
The Syrian Observatory for Human Rights said, citing unidentified reports, that scores of people were killed in Deir Balba on Saturday.
But the Britain-based watchdog said it could not verify these reports or give a specific casualty figure due to a cut in communications with the district, which had been besieged by government troops for days.