Syrian forces on Monday used fighter jets and rockets to pound rebel-held suburbs around Damascus International Airport, while rebels claim they have cut electricity in the facility.
Syrian television reported that troops struck hard at “terrorist bases” near the airport and the battle “to protect Damascus” continues.
The violence comes as Russian President Vladimir Putin is due to visit Turkey on Monday for a one-day trip, which will focus on the situation and the differences between the two countries over Syria.
Activists inside Damascus told DPA that the group of army “special forces” were seen deploying near the airport road and its outskirts.
“Our fighters are scoring advances near Damascus airport. Despite the heavy shelling, we managed to reach an area which supplies the airport with electricity and cut it off on the facility,” rebel commander Abu Nidal told DPA from Ghotta region, east of Damascus.
Tension prevailed on Monday after a clash erupted overnight between Lebanese troops and members of the Free Syrian Army as they were trying to infiltrate Syrian territories from Lebanon.
Airport officials were not available to comment on the claim, which comes as Egypt Air resumed its flights from Cairo to Damascus after a four-day halt.
In the northern province of Aleppo, a car bomb exploded near a military checkpoint, killing two soldiers and wounding 10 others.
Activists said rebels now control the main military checkpoint in Az-zoz, located on a highway that links Aleppo with Damascus.
Since the beginning of the Syrian revolt in March 2011, there have been frequent border violations, both by Syrian government forces and rebels fighting to overthrow President Bashar al-Assad.
Russia has been a main backer of the Syrian regime, while Turkey has supported the opposition.