Syria's army sent reinforcements to a rebel town near Damascus as clashes raged south of the capital Friday, hours after talks on the conflict between the US, Russia and UN ended without a breakthrough.
Meanwhile, UN chief Ban Ki-moon was due to visit Syrian refugees in Turkey before meeting in Ankara with President Abdullah Gul and Prime Minister Recep Tayyip Erdogan, key backers of the revolt against President Bashar al-Assad.
Inside Syria, activists feared a new ground assault on Damascus suburbs where military reinforcements poured in, said the Syrian Observatory for Human Rights.
"The army bombed orchards surrounding Daraya where military reinforcements are heading," said the Observatory, citing activists on the ground.
"Moadamiyet al-Sham was also violently pounded and large reinforcements were deployed apparently to attack the town," said the watchdog which gathers information from a network of activists and medics across the country.
Troops bombarded the southern districts of Damascus.
The outskirts of Damascus are at the heart of the fighting where the regime has launched an operation to reclaim territory within eight kilometres (five miles) of the city.
Analysts say the Assad regime wants to ensure it hold on the capital so that it can be in a position to negotiate a solution to the nearly 21-month conflict.
The Observatory said at least 77 people were killed on Thursday across the country, half of them in Damascus and its suburbs.
Amid the unrelenting violence, a 40-minute meeting in Dublin on Thursday between US Secretary of State Hillary Clinton, her Russian counterpart Sergei Lavrov and UN-Arab League peace envoy to Syria Lakhdar Brahimi ended with with "no sensational decisions".
Brahimi said all three agreed the situation was "very, very, very bad" in Syria, amid growing concern the conflict may take a gruesome new turn and see the regime unleash chemical weapons.
The three discussed "how we can work out hopefully a process that will get Syria back from the brink," said Brahimi.
A US State Department official said it was "a constructive discussion" and that the "next step will be a meeting in the next few days between special envoy Brahimi and senior officials from the United States and Russia to discuss the specifics of taking this work forward".
Clinton told reporters shortly before the talks: "We have been trying hard to work with Russia to stop the bloodshed in Syria and start a political transition toward a post-Assad Syrian future".
The three-way talks took place on the sidelines of a meeting of the Organization for Security and Cooperation in Europe.
It is likely the United States will move towards recognising the opposition National Coalition, set up in Qatar early last month, as the legitimate representative of the Syrian people at the meeting.
France last month became the first Western nation to do so.
The coalition suffered its first major setback on November 19, when Syria's jihadist Al-Nusra Front announced its refusal to recognise it.
Unknown before the start of the popular uprising in Syria in March 2011, Al-Nusra has claimed responsibility for the majority of suicide bombings that have rocked the country this year.
On Thursday, the US State Department expressed concern over the rising influence of fundamentalist groups in Syria, including Al-Nusra, which is said to have ties to Al-Qaeda.
"Although they make up a relatively small part of the opposition to Assad, we know that these groups, Al-Qaeda and their ilk, try to take advantage of exactly the kind of environment that Assad has fostered over the last year or so," spokesman Mark Toner said.