Israel's army on Sunday declared part of the Golan Heights a closed military zone, fearing battles on the Syrian side would spill over the ceasefire line.
An army spokeswoman told AFP the area around the Quneitra crossing was closed "for security reasons."
Speaking to AFP, security sources said they feared fighting between rebels and Syrian army forces would affect the area.
Rebels in southern Syria set up earlier this year the so-called Southern Front, including some 30,000 fighters from more than 55 mainstream rebel groups, and have claimed successes, notably in Quneitra.
The Quneitra crossing was recaptured by Syrian army forces last June after briefly falling into opposition hands.
More recently, the Syrian border has been less than quiet. In mid March, Syria claimed IAF airstrike killed one soldier and injured seven. Assad's army slammed the strike, threatening that "all options are open."
Defense Minister Moshe Ya'alon at the time warned Assad that he would "regret his actions" in threatening Israeli security, by allowing terrorists a free hand