Israeli Prime Minister Benjamin Netanyahu announced on Sunday that the 1974 UN-monitored Disengagement Agreement, which established a demilitarized buffer zone between Israel and Syria, has "collapsed."

Netanyahu made the comments during a visit to Mount Bental in the Israeli-annexed Golan Heights, a vantage point overlooking the Syrian border. He was accompanied by Defense Minister Israel Katz.

The prime minister said the collapse of Bashar al-Assad's government had "triggered a chain reaction across the Middle East."

Netanyahu noted that the Syrian administration's fall presents "new and very significant opportunities for Israel," while warning of the risks posed by the situation.

He said he had ordered Israeli forces to enter the buffer zone and assume positions to prevent hostile entities from taking hold of the area. "We will not allow any hostile force to establish itself on our border," he said, in an apparent message to Hayat Tahrir al-Sham, the group leading the rebel advances in Syria.

Netanyahu pledged that Israel would closely monitor developments and "do whatever is necessary to protect our borders and ensure our security." He also expressed hope for "a policy of good neighborliness" with Syria.

Katz, for his part, said he instructed the Israel Defense Forces, with the approval of the cabinet, to "take control of the buffer zone and key vantage points to ensure the protection of all Israeli communities in the Golan Heights -- both Jewish and Druze -- so that they will not be exposed to threats from the other side."

Since fighting with Hezbollah in Lebanon in October last year, Israel has escalated its airstrikes in Syria, claiming to have targeted Iran- and Hezbollah-affiliated militias and activities.