TEL AVIV, Israel — Infuriated by Moscow's decision last week to revive a long-shelved S-300 missile deal to Tehran, officials here reiterated Israel's right to target those batteries or any other high-end Russian arms transferred to regional terrorist organizations via Iran or Syria.

Prime Minister Benjamin Netanyahu, in an April 14 phone call with Russian President Vladimir Putin, expressed Israel's "grave concerns" that the S-300 sale "will only encourage Iranian aggression in the region [and will] the further undermine the stability of the Middle East."

Aside from making it much harder for Israel to wage prospective strikes against Tehran's nuclear network, officials here say the mobile air-and-missile defense batteries further expand the list of Russian arms viewed as legitimate targets should Iran or Syria attempt to retransfer such "balance breaking" capabilities to Lebanon-based Hezbollah.

In a terse statement following a nearly hour-long talk, Netanyahu assailed the sale of advanced weaponry to Iran as "the direct result of the dangerous deal on the table" between Iran and six world powers.

However, not included in the public readout of the conversation, sources here say, was Netanyahu's reminder to the Russian president of Israel's so-called "red lines" regarding attempts to retransfer Russian-origin systems via Iran or Syria to Hezbollah.

In an April 14 interview, one official said Israel is monitoring "active and ongoing leakage of Russian material," including SA-22 short-range and SA-17 medium-range air defense systems, via Syria to Iranian-backed Hezbollah allies in Lebanon.

"We've discussed this with our friends in Washington and Europe and made multiple demarches to Moscow over a period of weeks and months," the official said.

"Our red line policy is clear: We view unauthorized third-party transfers of Russian-origin equipment as legitimate targets," he added.

Netanyahu's office released a statement following the weekly Cabinet meeting April 19:

"Israel views with utmost gravity the supply of S-300 missiles from Russia to Iran, especially at a time when Iran is stepping up its aggression in the region and around the borders of the State of Israel. Israel also views with utmost gravity the fact that there is no reference to this aggression in the agreement being made between the major powers and Iran. There is no stipulation that this aggression be halted, whether at the start of the agreement or as a condition for the lifting of sanctions."

Referring to an April 18 military parade in Tehran, where Iran exhibited what it claimed was an indigenous version of an advanced air and missile defense system, Netanyahu said: "Every year the missiles are bigger and enhanced — in accuracy, strength and deadliness; however, one thing does not change. What does not change is the inscription 'Death to Israel' on the missiles.

"Against the threats that I have described, Israel will do whatever is necessary to defend the security of the state and its citizens."

Israeli officials have tacitly acknowledged a hand in some of at least five attacks in Syria attributed to Israel since January 2013; the latest came this last January in the Quneitra district near the Golan Heights.

At an April 2013 press conference in Tel Aviv with then-US Defense Secretary Chuck Hagel, Defense Minister Moshe Ya'alon said Israel "put very clear red lines to the Syrian regime: The first one, not to allow sophisticated weapons to be delivered or to be taken by rogue elements like Hezbollah and other rogue elements who are operating now in Syria. We proved it. When they crossed this red line, we operated. We acted."

Other lines, according to Ya'alon, involve transfer of chemical weapons to terrorist groups and any breaches of Israel's border with Syria by way of shots, shelling or attempted infiltrations.

In the weeks ahead, Israel aims to gain guarantees from Moscow that it will impose strict end-use restrictions on S-300s shipped to Iran in parallel with ongoing efforts to improve terms of a probable comprehensive nuclear deal with Iran.

"Russian authorization to renew the S-300 deal that had been frozen in recent years is a direct result of the framework deal reached in Lausanne Laussane that we have been warning about," Ya'alon said on April 14.

"This subject is very disturbing and is one of the huge holes in the deal — actually it's outside of the framework agreement… I hope there will still be time in the coming months to correct this," he added.

At the same time, a Russian diplomatic interviewed on April 16 said Moscow expects to secure Israeli assurances not to engage in preemptive strikes of Russian arms en route to Iran and other bonafide client states.

He said that Putin's decision lifts a voluntary ban "on the transit through Russian territory, including airlift, and the export from the Russian Federation to the Islamic Republic of Iran, and also the transfer to the Islamic Republic of Iran outside the territory of the Russian Federation, both by sea and by air."

The diplomat noted that the ban on the estimated US $800 million deal was imposed by Putin's predecessor, former President Dmitry Medvedev, due in large part to heavy pressure from Washington and Tel Aviv.

Finally, he echoed Russian Foreign Minister Sergey Lavrov's assurances that the S-300 is purely defensive. "As the foreign minister said, this system is not designed for attacks. It will not put at risk the security of any state in the region, including Israel."

In his first visit to Israel as Russia's president exactly a decade ago, in April 2005, Putin acknowledged what, at the time, were Israeli concerns over a possible S-300 sale to Syria. As a compromise, Putin said he had allowed the sale of short-range Strelet missiles instead.

"I am aware of Israel's concerns regarding the possibility that the missiles will reach the hands of terror organizations in Lebanon. However, these concerns are groundless… For these missiles to hit you, you will need to enter Syrian territory," Putin told then- Israeli President Moshe Katsav.