The closure of the Nassib crossing in 2015 cut a crucial transit route for hundreds of trucks a day transporting goods between Turkey and the Gulf, and Lebanon and the Gulf, in multi-billion dollar annual trade.
Israel has been on high alert as Assad's forces advance on rebels in the vicinity of the Golan Heights, much of which Israel captured from Syria in 1967 and annexed in a move not recognised internationally.
The United States on Thursday reiterated its demand that the zone be respected, warning Assad and his Russian allies of "serious repercussions" of violations. It accused Damascus of initiating air strikes, artillery and rocket attacks.
Over a 100 missiles rocked the Syrian capital of Damascus and surrounding areas on Saturday as Western forces launched a coordinated and targeted attack on the country. Here's everything you need to know.
Turkey launched "Operation Olive Branch" two weeks ago targeting the YPG Kurdish militia in Afrin, opening a new front in Syria's seven-year-old, multi-sided civil war. Russia is the main backer of Syrian President Bashar al-Assad.
The Turkey-based Syrian National Coalition (SNC) political opposition group said the congress was an attempt to circumvent "the international desire for a political transition" and the United Nations-led political track in Geneva.
Since the beginning of Syria’s civil war, the Bashar Al-Assad government has targeted and killed hundreds of medical workers. Many have fled. This is the story of one doctor, Mohammed al-Bardan, who did not.