The US Central Intelligence Agency director John O. Brennan arrived in Israel Thursday evening to discuss Syrian crisis with Israeli Defense Minister Moshe Ya' alon, Israel's Channel 2 Television reported.

This is Brennan's first visit to the country since US President Barack Obama appointed him to the post in March. He is scheduled to meet with Defense Minister Moshe Ya'alon and receive briefings from defense officials on the Syrian crisis and its ramifications, Channel 2 said.

Ya'alon is expected to reiterate Israel's policy, which maintains that while it wants no part in Syria's war, it is determined to prevent arms transfers from that country to Lebanon's Hezbollah, according to Channel 2.

The visit of CIA chief to Israel comes a day after the New York Times quoted an unnamed senior Israeli official as saying that his country will continue to take military action to foil attempts to transfer advanced weaponry to Hezbollah.

In an explicit threat to Syrian President Bashar Assad, the official warned that if the latter reacts to recent alleged Israeli air strikes that targeted Iranian shipments of missiles to Hezbollah, he would risk the collapse of his regime.

"If he reacts by attacking Israel, or tries to strike Israel through his terrorist proxies, he will risk forfeiting his regime, for Israel will retaliate," the official was quoted as saying.

Meanwhile, Prime Minister Benjamin Netanyahu's efforts to convince Russian President Vladimir Putin not to supply Syria with advanced S-300 anti-aircraft missiles had failed, Channel 2 reported.

The report quoted Russian Foreign Minister Sergei Lavrov as announcing Thursday evening that Moscow remains committed to the deal it signed with Damascus for the sale of the missiles, explaining that "while we have no intention to violate international law, we don't want to tarnish our good reputation as a credible supplier of arms."

The announcement came two days after Netanyahu met with Putin in Sochi to discuss Syrian crisis, describing events in the region as "very stormy, unstable and explosive" and clarifying that Israel views the S-300 as a "tie-breaking" weapon.