BEIRUT - Syrian rebels battled forces loyal to President Bashar Assad just outside Damascus on Thursday, restricting access to its international airport, and the Dubai-based Emirates airline suspended flights to the Syrian capital.A rebel fighter who identified himself as Abu Omar, a member of the Jund Allah brigade, told Reuters that insurgents fired mortars at the airport's runways and were blocking the road linking it with the capital.Assad prepares for showdown with rebels around DamascusA senior European Union official said that Assad appeared to be preparing for a military showdown around Damascus, possibly by isolating the city with a network of checkpoints."The rebels are gaining ground but it is still rather slow. We are not witnessing the last days yet," the official said on condition of anonymity."On the outskirts of Damascus, there are mortars and more attacks. The regime is thinking of protecting itself ... with checkpoints in the next few days ... (It) seems the regime is preparing for major battle on Damascus."The Syrian security source, who is from the elite 4th Armoured Division, said one of the aims of the army's operation was to completely cut off the suburbs - where rebels are in control - from the city center.In the north of the country, rebel units launched an offensive to seize an army base close to the main north-south highway that would allow them to block troop movements and cut Assad's main supply route to Aleppo, Syria's biggest city.The Observatory said that rebel units from around Idlib province massed early on Thursday morning to attack Wadi al-Deif, a base east of the rebel-held town of Maarat al-Numan.Wadi al-Deif has been a thorn in the side of rebel units who first besieged the station in October but met fierce resistance from government forces, backed up by air strikes.Assad is fighting an insurgency that grew out of peaceful demonstrations for democratic reform but escalated, after a military crackdown on protesters, into a civil war in which 40,000 people have been killed.He said insurgents were not inside the airport but were able to block access to and from it.Another source in a Damascus rebel unit said mortars had been used in clashes near the airport but did not know whether rebels had fired mortars directly at the airport.Their accounts could not be immediately verified because of severe restrictions on media access to Syria.Two Austrian soldiers in a UN peacekeeping force deployed in the Golan Heights, disputed by Syria and Israel, were wounded when their convoy came under fire near the Damascus airport, the defense ministry said in Vienna.An official at EgyptAir said it had cancelled its Friday flight to Damascus due to the "deteriorating situation" around the airport. He said the airline would hold an urgent meeting in the next few hours with Egyptian officials to discuss halting all flights between Egypt and Syria.Residents also reported Internet connections in the capital were down and mobile and land telephone lines working only sporadically in what appeared to be the worst disruption to communications in Syria since an uprising began 20 months ago.Syria's minister of information claimed that "terrorists", not the state, were responsible for a countrywide Internet outage, a pro-government TV station said.The past two weeks have seen rebels overrunning army bases across Syria, exposing Assad's loss of control in northern and eastern regions despite the devastating air power that he has used to bombard opposition strongholds.Rebels and activists said the fighting along the road to Damascus airport, southeast of the capital, was heavier in that area than at any other time in the conflict."No one can come in or out of the airport," said Abu Omar.The Syrian Observatory for Human Rights, a opposition monitoring group, said clashes were particularly intense in Babbila, a suburb bordering the insurgent stronghold of Tadamon.Nabeel al-Ameer, a spokesman for the rebel Military Council in Damascus, said that a large number of army reinforcements had arrived along the road after three days of scattered clashes ending with rebels seizing side streets to the north of it.Emirates said it was suspending daily flights to Damascus "until further notice", but other airlines continued operations.Airport sources in Cairo said an EgyptAir flight that left at 1:30 p.m. (1130 GMT) had landed in Damascus on schedule but the pilot was instructed to take off back to Egypt. An official said the plane returned to Cairo 45 minutes ahead of schedule.Elsewhere in Damascus, warplanes bombed Kafr Souseh and Daraya, two neighborhoods that fringe the center of the city where rebels have managed to hide out and ambush army units, according to opposition activists.