EgyptAir and Emirates airline have suspended flights to Damascus because of the security situation.
The news comes as some rebel sources claim to have hit the runway in the Syrian capital with rockets, while other Free Syrian Army members said they had not attacked the airport but did have control of the main road to the airport.
Syria’s Information Ministry disputed this saying the main motorway to Damascus international airport is safe.
Heavy fighting was seen around the country. It was reported that in areas of Damascus, Homs and Aleppo government warplanes were firing on rebel locations on Wednesday and Thursday.
On Wednesday amateur footage purportedly shot in Aleppo claimed to show a destroyed MiG jet crashing to the ground.
But despite Assad’s forces overwhelming air superiority they seem unable to quash the rebel advance.
Amid the fighting, the UN and Arab League special envoy to Syria, Laktar Brahimi, said the only way towards a lasting peace would be to put boots on the ground:
“No doubt what is urgently needed is a ceasefire that can hold. From the experience of the Arab League, the experience of UNSMIS, the little experience of the ceasefire that I called for – a ceasefire will not hold unless it is very very strongly observed. That I believe will require a peacekeeping mission,” he said.
Thursday also saw the biggest communications breakdown in the country during the 20-month-conflict.
Renesys, a US company that tracks worldwide internet traffic said Syria’s international Internet connectivity shut down completely around midday, while mobiles and landlines were functioning only intermittently.
The reason for this loss of connection is unclear.