International peace envoy Lakhdar Brahimi warned after meeting President Bashar al-Assad on Saturday that the worsening conflict in Syria threatens both the region and the world at large.
Russia, a strong ally of Syria, insisted it was not "clinging" to any particular leader in Syria, but warned it would block any new UN Security Council resolution aimed at pressuring Assad, a long-time Moscow ally.
"The crisis is dangerous and getting worse, and it is a threat to the Syrian people, the region and the world," said the newly appointed Brahimi, who took over as envoy earlier this month from former UN chief Kofi Annan.
Assad, quoted by state television, said dialogue between Syrians held the key to a solution and called on foreign countries to stop supplying arms to his foes.
"The real problem in Syria is that of combining politics with the work being done on the ground," he said. "The political work continues, in particular by calling for dialogue between Syrians based on the aspirations of all Syrians.
"The success of political action is dependent on putting pressure on the countries that finance and train the terrorists, and which bring weapons into Syria, until they stop doing so," Assad said.
Eighteen months into Syria's deadly conflict and without an end in sight, Assad said his government would "cooperate with all sincere efforts to solve the crisis, so long as the efforts are neutral and independent."
Brahimi, a 78-year-old veteran Algerian troubleshooter, has also met Foreign Minister Walid Muallem and members of the officially tolerated opposition since arriving in Damascus on Thursday.
"There is need for all parties to unite their efforts to find a solution for the crisis, given Syria's strategic importance... and the crisis's influence over the whole region," Brahimi said.
"The solution can only come from the Syrian people."
He said he currently had "no plan" to tackle the crisis, but a strategy will be "set... after listening to all internal, regional and international parties."
Brahimi warned on arrival that the conflict is "getting worse." He is on his first Damascus visit since replacing Annan who quit after a hard-sought peace deal he brokered became a dead letter.
Brahimi on Friday met Syrian opposition figures who said he was bringing "new ideas" to the peace effort.
He met opposition groups tolerated by Assad's regime such as the National Coordination Committee for Democratic Change, which groups Arab nationalists, Kurds and socialists.
The group said it was sending a delegation on Saturday to China, a key Damascus ally, to urge Beijing to "put pressure on the regime to stop the violence, free detainees and allow peaceful protests."
But Russian Deputy Foreign Minister Gennady Gatilov insisted on Saturday Moscow was not "clinging" to any individual leader in Syria.
Yet he signalled that Russia would block any new UN Security Council efforts to put pressure on Assad after 18 months of violence that activists say has claimed more than 27,000 lives. The United Nations puts the toll at 20,000.
"It is only through the political process -- and not through any decision of the UN Security Council -- that the Syrians should determine the future of their state and its make-up," he said.
Pope Benedict XVI, on a visit to neighbouring Lebanon, had words of praise for young Syrians on Saturday.
"I want to tell you how much I admire your courage," the 85-year-old pontiff said, but added that he was "sad because of your suffering and your bereavement."
The Syrian Observatory for Human Rights, which gathers information from a network of activists on the ground, said at least 107 people, including 64 civilians, were killed nationwide on Saturday.
It said 132 died on Friday, including 100 civilians, 18 of them in Damascus.
On the ground, overnight air strikes killed at least 12 civilians and wounded around 60 in Al-Bab in northern Syria, doctors in the rebel-held town told AFP.
Two fighter jets carried out a series of raids on the town between 4 pm (1300 GMT) on Friday and 4 am (0100 GMT) on Saturday, hitting homes and empty school buildings, a hospital doctor said, asking not to be identified.
In one home four people lost their lives, three of them women, the father of one of those killed told AFP. Residents said there were no rebels in any of the buildings hit.
Clashes also broke out in Damascus and the northern city of Aleppo where the army battled rebels at entrances to the rebel-held Bustan al-Basha district and helicopter gunships attacked the opposition bastions of Hanano and Sakhur, the Observatory said.
After a week of fighting over the central district of Midan, the army had taken most of the area and set up checkpoints for the first time, an AFP correspondent said.
The Local Coordination Committees, a network of opposition activists on the ground, reported an unknown number of people killed or trapped under the rubble of a three-storey residential building that collapsed when the Sheikh Fares neighbourhood was shelled.
Near Damascus, five rebels were killed by shelling and sniper fire in the southern suburb of Al-Hajar al-Aswad, the Observatory said.
Three civilians, including two women, were killed in shelling in the northwest province of Idlib, while in the eastern city of Deir Ezzor a 14-year-old was killed in shelling and the town of Albu Kamal came under fresh bombardment, it said.