(AFP) - Lebanese Shiite movement Hezbollah hailed Syria's air defenses after they downed an Israeli fighter jet on Saturday, saying it marked the start of a "new strategic era".

"This is the beginning of a new strategic era which puts an end to the violation of Syrian airspace and territory," Hezbollah said in a statement published by Lebanon's ANI news agency.

Hezbollah, which is backing Syrian President Bashar al-Assad's in his country's civil war, praised the "vigilance of the Syrian army" and said it had "bravely blocked Israeli warplanes and downed an F16".

Israel struck what it said were Iranian targets inside Syria on Saturday in "large-scale" raids after an Israeli warplane crashed under fire from Syrian air defenses, its military said.

The confrontation was the most serious between arch-foes Israel and Iran since the civil war in Syria began in 2011.

Israel said the raids came after it intercepted what it said was an Iranian drone entering its airspace from Syria.

Iran denounced Israeli "lies" and said Syria had the right to self-defence in response to Israeli strikes. Separately, Iran issued a joint statement with the Syrian regime's other main allies -- Russia and Hezbollah -- denying Israel's account of the drone.