Israel, too, may feel emboldened by US President Donald Trump's decision to withdraw from the 2015 Iran nuclear deal.
More than 20 rockets were fired from Syria toward Israeli territory late Wednesday, often criss-crossing across the clear night skies.
Israel has posted Iron Dome short-range air defenses on the Golan, local media said, suggesting that the anticipated attack could be by ground-to-ground rockets or mortars.
Hezbollah leader Sayyed Hasan Nasrallah said Monday that Israeli forces were attacked in the occupied Golan Heights for the first time since 1973 last week.
Israel says it struck dozens of Iranian targets overnight in response to a rocket barrage on Israeli positions in the Golan Heights. Gen. Qasem Soleimani, often seen as the face of Iran's regional ambitions.
Syria's state news agency SANA said opposition fighters who chose to stay in the suburbs will hand over the weapons and return to normal life.
"Dozens of missiles were shot down in Syrian airspace by anti-aircraft systems", the official SANA news agency said, without specifying if the missiles were aimed at the Syrian capital, where explosions were heard early Thursday.
Assad spoke in an interview with the Greek Kathimerini newspaper published Thursday, before Israel carried out airstrikes in Syria in response to what it said was a cross-border rocket attack by Iranian forces.
The targets included rocket launchers, intelligence posts, military command posts, and weapons depots.
Some reports suggest that an earlier Israeli air strike already destroyed Iranian air defences deployed to Syria. But it then went on to strike at most, if not all, of the Iranian installations it knows about in Syria.
Netanyahu says he and Putin also discussed the USA administration's decision to withdraw from the Iranian nuclear deal, but says the conversation focused mostly on Iran's effort to turn Syria into a forward base to attack Israel.
An official with the Iran-led regional alliance supporting regime head Bashar Assad said the strike targeted a regime position, but killed a Syrian man and his wife who happened to be passing by in their vehicle. Israel has not commented on the strike. Israel opened bomb shelters in the Golan Heights, but did not instruct people to enter the shelters.
Russian President Vladimir Putin and German Chancellor Angela Merkel spoke Friday and underlined their aim of preserving the deal and peace in the Mideast. The incoming attack set off air raid sirens in the Israeli-controlled Golan, which was captured from Syria in the 1967 war. "Certainly, it is Israel's right to take such steps as necessary to defend itself against this aggression".
Israel and Iran have long fought each other through proxies, and with the new exchange each seemed to be sending a warning that a direct clash between them could swiftly escalate.
"The situation, unfortunately, is very acute".
In a statement issued as Israel's security cabinet met, Israeli Prime Minister Benjamin Netanyahu said the strike sent a "clear message" that "whoever attacks us - we will attack them sevenfold and whoever prepares to attack us - we will act against them first".
Russian Federation and Israel coordinate their actions within Syria for the goal of deconfliction.
Israel has often reiterated one of its red lines that it will not allow Iran to establish a military presence in Syria.
As dawn broke Thursday morning, the sounds of conflict had dissipated, though it remained unclear whether these two sworn enemies would continue fighting, or if the tit-for-tat had ended.
Israel's top general, Gadi Eizenkott, canceled a scheduled appearance at an annual security conference and was conferring with Defense Minister Avigdor Lieberman and other national security chiefs, officials said.