Israeli Prime Minister Benjamin Netanyahu flew to Russia on Tuesday amid concern that Moscow plans to sell advanced air defense systems to Syrian President Bashar al-Assad.
If sent to Syria, the S-300 anti-aircraft missile system - with a range of 125 miles - would complicate possible foreign military intervention into Syria's civil war, especially airstrikes.
Russia says it has no plans to sell the S-300 to Assad's regime, but under an extant contract it could deliver the anti-aircraft system.
"Russia is not planning to sell,” said Foreign Minister Sergei Lavrov said last week. “Russia already sold [the weapons] a long time ago. It has signed the contracts and is completing deliveries, in line with the agreed contracts, of equipment that is anti-aircraft technology."
Syria reportedly paid a first installment of $900 million to Russia for six launchers and around 144 missiles.
More from GlobalPost: US concerned Russia may sell air-defense system to Syria: report
Netanyahu, who is meeting Putin in the Black Sea town of Sochi, is also expected to speak with the Russian leader about Iran's much-debated nuclear program and address Israel's concern that Russian weapons could fall into the hands of militant groups in Lebanon.
“The region around us is very unstable and explosive, and therefore I am glad for the opportunity to examine together new ways to stabilize the area and bring security and stability to the area,” Netanyahu said in his opening remarks.
Netanyahu and Putin's meeting follows US President Barack Obama and British Prime Minister David Cameron's conference in Washington, DC, where Obama voiced hope that Russia would pressure Assad to find a diplomatic solution.
More from GlobalPost: Obama, Cameron hold talks on Syria, EU, G8
"As a leader on the world stage, Russia has an interest, as well as an obligation, to try to resolve this issue in a way that can lead to the kind of outcome that we’d all like to see over the long term,” Obama said.
The upcoming diplomatic conference, dubbed “Geneva2,” has been backed by Washington and Moscow in an effort to bring Assad and the Syrian opposition to the negotiating table, but neither side has signed on.
"It's not easy, there must be people from the opposition and people close to the regime who do not have blood on their hands," said French Foreign Minister Laurent Fabius.
US Secretary of State John Kerry said the international conference on Syria would happen sometime in early June, and on Tuesday suggested he expected both sides of the conflict to attend.
On whether or not Assad would show for talks, Kerry said, "If he decides not to come to the table it will be another one of President Assad's gross miscalculations. Now, I don't believe that that is the case at this moment."
Following the meeting, it emerged that the Israeli Defense Force (IDF) chief of intelligence, Gen. Aviv Kochavi, had accompanied Netanyahu to Russia, ays GlobalPost's Noga Tarnopolsky in Jerusalem.
"Gen. Kochavi's presesnsce suggests that fresh and authoritative intelligence" was most likely transmitted to Putin from the Israeli side, Tarnopolsky says.
From the Israeli and American points of view, Russia and Iran's ongoing support of Assad is an "obstacle to any possible solution to the Syrian civil war," she said. "With Iran, there is no dialogue, which leaves and Russia and Russian interests as the clearest avenue" for the Israelis to approach.
More from GlobalPost: Cameron, Putin discuss Syria amid new push to end war
Senior correspondent, Noga Tarnopolsky, contributed reporting from Jerusalem.