President Vladimir Putin's talks with Israeli Prime Minister Benjamin Netanyahu in Russia on Tuesday will focus on the situation in Syria, the Kremlin said.

Netanyahu's visit comes after Israel expressed concern over what its officials say is an imminent sale of Russian S-300 anti-aircraft missiles to Syria. Israel has asked Russia to stop supplying "game-changing" weapons to its ally, Syrian President Bashar Assad.

Russia has continued to supply Assad's regime with weapons, despite the civil war there, rejecting Western demands to halt such sales and arguing that they haven't violated international law.

Russian arms deliveries have included air defense missiles and artillery systems, but Moscow has refrained from providing Damascus with the advanced S-300. The powerful weapon has a range of up to 200 kilometers (125 miles) and a capability to track down and strike multiple targets simultaneously with lethal efficiency. It would mean a quantum leap in the Syrian air defense capability and pose a strong challenge to any possible aerial campaign.

Speaking in Warsaw on Friday, Russia's Foreign Minister Sergey Lavrov said that Russia was completing the delivery of air defense systems to Syria under earlier signed contracts, but avoided specifying whether the S-300 batteries are among them.

Earlier this month, Lavrov met with U.S. Secretary of State John Kerry, and they announced they would host an international conference during which Syrian government officials and rebels will be offered the chance of naming an interim government.

On Friday, Putin met with British Prime Minister David Cameron in Moscow for talks that also centered on Syria. Cameron said they are committed to developing a proposal for a Syrian transitional government. The British leader didn't say if the missile issue was discussed, but Russian news agencies said that Moscow insisted that it would honor all earlier signed contracts.

Russia media reports have said that Russia signed a contract for the delivery of the S-300s to Syria a few years ago, but later shelved it under pressure from Israel and the West.

Vyacheslav Davidenko, a spokesman for the Russia's Rosoboronexport state arms trader, refused to comment on the issue Monday.