State media blamed the early-morning "terrorist" bombing at the entrance to the mixed Christian-Druze suburb of Jaramana in which 16 civilians were wounded.
The Syrian Observatory for Human Rights said a suicide bomber from the Al-Qaeda-linked Al-Nusra Front detonated an explosives-packed car at the checkpoint between Jaramana and rebel-held Mleha.
Fighting raged for much of the day, with rebel mortar fire hitting Jaramana and regime aircraft striking back, according to the Britain-based Observatory, which relies on activists and medics on the ground.
At least 16 soldiers and 15 jihadists were killed, it said.
One resident said the fighting was "unprecedented" since Syria's conflict erupted in March 2011, telling AFP by telephone: "It is very violent; we can hear automatic weapons fire, mortar rounds, bombardments."
The conflict, which erupted after President Bashar al-Assad launched a bloody crackdown on Arab Spring-inspired democracy protests, is believed to have killed more than 115,000 people.
Millions more have been forced to flee the country and hundreds of thousands are trapped by the fighting.
UN humanitarian chief Valerie Amos on Saturday called for a ceasefire in the Damascus suburb of Moadamiyet al-Sham, where thousands of people were evacuated last week and where she said "the same number or more remain trapped."
The United States a day earlier had condemned the regime's relentless siege of rebel-held Moadamiyet al-Sham and Eastern Ghouta on the capital's outskirts, and said it must allow relief convoys in.
There were "unprecedented reports of children dying of malnutrition-related causes in areas that are only a few miles from Bashar al-Assad's palace in Damascus," said State Department spokeswoman Jen Psaki.
"The regime's deliberate prevention of the delivery of lifesaving humanitarian supplies to thousands of civilians is unconscionable."
Residents of Moadamiyet al-Sham told AFP this week that food is running desperately low and that children have died in some areas.
In another sign of Syria's growing misery, the World Health Organisation said it had detected two possible cases of polio in the eastern Deir Ezzor province which, if confirmed, would be the country's first known cases since 1999.
Envoy says 'intense efforts' for peace talks
UN-Arab League envoy Lakhdar Brahimi, meanwhile, met with Egypt's foreign minister Saturday, saying "intense efforts" were under way to convene Syrian peace talks in Geneva next month.
But prospects for the meeting remain dim, with Syria's opposition divided and due to vote next week on whether to take part, and Assad's government insisting he will not bow to the rebels' chief demand and step down.
Brahimi was to meet the head of the Arab League on Sunday and then head for talks in Syria itself and Iran, a key backer of the Assad regime.
The push for the Geneva talks will also be high on the agenda of US Secretary of State John Kerry, who heads to Europe to attend a "Friends of Syria" meeting in Britain on Tuesday.
The renewed push for peace talks comes after Damascus accepted in September a US-Russian deal to hand over its chemical arsenal for destruction.
But the political opposition remains divided amid recent clashes between mainstream fighters and jihadists, as well as growing rifts between rebels fighting on the ground and the external opposition.
The main National Coalition opposition bloc said members will decide next week whether to attend the Geneva talks, while the Syrian National Council, a coalition member, has threatened to quit if they do.
Meanwhile, Al-Qaeda loyalists of the Islamic State of Iraq and the Levant (ISIS) have captured at least 35 rebels from the mainstream Free Syrian Army in the northern city of Aleppo, the Observatory said.
The two Turkish pilots were handed over to Lebanese authorities, state media reported, and Foreign Minister Adnan Mansour said from Beirut airport he was awaiting the arrival of the nine Lebanese Shiite pilgrims from Turkey.
Syrian rebels had demanded the release of some 200 prisoners from Syrian jails in exchange for freeing the pilgrims. It was not immediately clear if those releases went ahead.