Israel's Defence Minister Avigdor Lieberman has warned Syria not to repeat attempts to shoot down Israeli bombers after anti-aircraft missiles were fired at Israeli planes near Palmyra on Friday (17 March). Syria claimed the planes attacked a Syrian military site, whereas Israel claims it was targeting a shipment of advanced weaponry destined for Hezbollah forces in Lebanon.

Syrian sources claim to have shot down one Israeli plane and hit another, claims Israel dismissed as "absolutely untrue". Speaking on public radio on Sunday Lieberman said: "The next time the Syrians use their air defence systems against our planes we will destroy them without the slightest hesitation."

Syria's regime of Bashar al-Assad is allied with fellow Shia Muslim nation Iran, who have been equipping Hezbollah with weaponry and military expertise. Iran claims Hezbollah are fighting Isis, but Israel is concerned that advanced weaponry may be used against it.

"Our central problem, and this above and beyond all of the other issues, is the transfer of advanced weapons from Syria to Lebanon," said Lieberman. "Every time we identify a transfer like this, we will work to prevent the transfer of game-changing weapons. On this issue, there will not be any compromise."

Israeli Prime Minister Benjamin Netanyahu also defended the attacks.

"When we identify attempts to transfer advanced weapons to Hezbollah and we have intelligence and it is operationally feasible, we act to prevent it," according to the Times of Israel. "That's how it was yesterday and that's how we shall continue to act. We are fully determined and the evidence of that it that we are acting. Everybody must take that into account – everybody."

It is rare for Israel to publicly acknowledge air strikes inside Syria, with whom Israel is still technically at war. It is also rare for Syria to respond by firing back. Assaf Orion, senior research fellow at Israel's Institute for National Security Studies, told the Times of Israel Syria's regime might be emboldened by its strengthening ties with Iran and Russia.

"The Syrian regime is trying to tell Israel it can't stand it anymore and those actions will not be free of charge," said Orion. "[Assad] is saying: 'Don't push me. I am not as weak as I used to be.'"

Syria soldiers Palmyra 2017
Syrian army soldiers carry flags in the amphitheatre of the historic city of Palmyra, Syria, in March 2017 REUTERS/Omar Sanadiki