Peace envoy Lakhdar Brahimi Monday held talks with Syria's president on the "worrying" situation in the country, as Damascus fended off accusations its forces bombed a bakery killing dozens of civilians.
Activists meanwhile accused President Bashar al-Assad's regime of unleashing killer gas bombs in the central city of Homs, even as Russia downplayed fears that Syrian forces would use chemical weapons against the armed opposition.
"I had the honour to meet the president and as usual we exchanged views on the many steps to be taken in the future," Brahimi told reporters at his Damascus hotel, a day after he arrived to launch a fresh bid to end the conflict roiling Syria.
The UN-Arab League envoy said the Syrian crisis was "always worrying", with more than 44 000 people killed since the uprising against Assad's regime erupted in March last year, according to the Syrian Observatory for Human Rights, which relies on a network of medics and activists on the ground.
Brahimi expressed hope that "all parties are in favour of a solution that draws Syrian people together."
"Assad expressed his views on the situation and I told him about my meetings with leaders in the region and outside," said the veteran Algerian diplomat who took over his present task from former UN chief Kofi Annan.
Assad described the meeting as "friendly and constructive," according to state television.
"The government is committed to ensure the success of all efforts aimed at protecting the sovereignty and independence of the country," Assad said.
Brahimi last visited Syria on October 19 in a bid to clinch a temporary ceasefire for the Muslim feast of Eid al-Adha. Despite pledges, the truce did not hold.
His arrival in Syria on Sunday coincided with reports by activists that at least 60 people were killed in a regime air strike on a bakery in the town of Halfaya, in the central province of Hama.
The activists said the attack, in which many women and children were killed, amounted to a "massacre".
The official news agency SANA however on Monday blamed the killings on an "armed terrorist group" - the term used by the regime to describe rebels fighting to topple Assad.
"An armed terrorist group attacked the town of Halfaya committing crimes against the population, killing many women and children," SANA said, adding that the Syrian army intervened during the assault and "killed and wounded many terrorists".
"Terrorists then shot video images to accuse the Syrian army when the international envoy Lakhdar Brahimi arrived in Syria," the agency said.
Video footage posted online by activists showed a bombed one-storey block and a crater in the road.
Bloodied bodies lay on the road, while others could be seen in the rubble. Men carried victims out on their backs, among them at least one woman. The video could not immediately be verified.
With no let-up in sight to the violence despite Brahimi's latest efforts, the Britain-based Observatory reported that warplanes launched several strikes in the Eastern Ghuta area near Damascus after fierce overnight battles in the capital.
It also reported shelling in the province of Hama - site of Sunday's gruesome killings.
The Observatory said that six rebels died in Homs Sunday night after inhaling "odorless gas and white smoke" emanating from bombs deployed by regime forces in clashes with rebels.
"These are not chemical weapons, but we do not know whether they are internationally prohibited," Observatory director Rami Abdel Rahman told AFP.
Russia, one of the few staunch allies of Syria, downplayed fears of chemical weapons being deployed.
"I do not believe Syria would use chemical weapons," Foreign Minister Sergei Lavrov told English-language television channel RT. "It would be a political suicide for the government if it does."