Israel has issued a chilling threat to Iran as fears grow of an ever increasing escalation in hostilities. The region stands on the brink of a major conflict after Iran launched an unprecedented aerial bombardment on its foe.

       The Israeli army says Tehran launched over 300 drones and missiles in the early hours of Sunday, of which 99 percent were shot down by air defence systems.

       The attack has led to a ratcheting up of aggressive and militant rhetoric between the warring parties.

       Leaks from an Israeli war cabinet meeting suggest Benjamin Netanyahu is preparing to retaliate with a "painful strike" against Iran.

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       And recent comments from an IDF spokesperson at a press conference on Tuesday would appear to confirm that Israel will not allow Tehran's brazen attack to go unanswered.

       Rear Admiral Daniel Hagari said his country "cannot stand still from this kind of aggression" and that Iran would not get off "scot-free".

       Iran says its attack was a just response to an Israeli missile strike on its Syrian Embassy, which killed two of its most senior generals.

       Tehran said it considered the matter now closed unless it is once again provoked by Israel.

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       Iranian President Ebrahim Raisi warned Netanyahu that Israel could expect a "painful response" if it retaliated.

       At the same time, Abolfazl Amoue, a member of Iran's National Security Committee, threatened to unleash a secret new weapon that has never been used before.

       Tehran fired around 120 ballistic missiles in its aerial onslaught in the Jewish state. One rocket can carry over 880 pounds of explosives.

       The IDF said in a statement: "The world must recognise Iran’s attack could’ve ended very differently.

       "It’s thanks to our advanced aerial defence systems and the help of our international partners that the attack was successfully thwarted."

       Speculation is rife that Israel will try and target Iran's nuclear facilities in any response to Sunday's attack.

       However, Professor Yossi Mekelberg - an expert on Israeli politics - considered an attack on Tehran's atomic facilities as unlikely, telling the Express.co.uk it would be seen as an "escalation on almost the highest level".