Prime Minister Binyamin Netanyahu signaled Monday that Israel would take military action in Syria when it sees fit as it seeks to ensure Iran-backed forces stay away from its territory.
Israel has long accused Iran, its main enemy, of taking advantage of Syria's civil war to send its Revolutionary Guard and its Lebanese Shiite ally, the Hezbollah terrorist group, into southern Syria, close to the border with the Jewish state.
It has sought to avoid being dragged into the fighting but has reportedly carried out dozens of air strikes to prevent arms deliveries to Hezbollah, which fights alongside Syrian President Bashar al-Assad's forces.
Israel was reportedly seeking a buffer zone in southern Syria near Israeli territory of some 50 kilometers (30 miles), but an agreement reached last week between the United States, Russia and Jordan fell short of that demand, Israeli media said.
"I have made it clear to our friends, first of all in Washington and also to our friends in Moscow, that Israel will act in Syria -- including in southern Syria -- according to our understanding and according to our security needs," Netanyahu told senior members of his Likud party, according to a party statement.
"This is what is happening and this is what will continue to happen."
Netanyahu's statement followed reports that a recent cease-fire agreement between the US, Russia, and Jordan would leave Iranian-backed militias just three miles from the Israeli border.
The November 8 agreement seeks to build on a ceasefire already in place in southwestern Syria.
On Saturday the Israeli military said it shot down a Syrian drone carrying out a reconnaissance mission over the Golan Heights.
"We will not allow the consolidation of a Shiite axis in Syria" as a base for operations against Israel, Israeli Defense Minister Avigdor Liberman said in a statement after the incident.
In September, Israel's military shot down what it said was an Iranian-made drone operated by arch-foe Hezbollah on a similar mission.