"We inflicted on Saturday a heavy blow to Iranian and Syrian forces," Netanyahu said at the start of a cabinet meeting, referring to major Israeli air raids in Syria.

"We made clear to everyone that our rules of engagement will not change in any way. We will continue to harm anyone who tries to harm us. This was our policy and this will remain our policy."

Israel said its raids were against both Syrian and Iranian targets in Syria.

The raids came after an Israeli F16 fighter jet was shot down by Syrian air defences. The pilots survived, but it was the first time Israel had lost a warplane in battle since 1982.

The strikes began with Israel shooting down what it described as an Iranian drone that had entered its airspace from Syria -- calling it an "attack."

Iran denied the allegations regarding the drone and said Syria had the right to defend itself against Israeli attacks.