A Russian S-300 anti-aircraft missile system. (AP)

After the Kremlin announced the sale of the advanced system to Iran a year ago, Prime Minister Benjamin Netanyahu spoke with Russian President Vladimir Putin and expressed Israel’s “grave concerns” regarding the deal. Netanyahu stressed the sale will “only encourage Iranian aggression in the region” and “further undermine the stability of the Middle East.”

A senior Russian official stated that Moscow has started delivering S-300 air defense missile systems to Iran.

Deputy Prime Minister Dmitry Rogozin, who spoke on Monday on Ekho Moskvy radio, wouldn’t say how many systems have been delivered or provide any other specifics.

In 2010, Russia froze a deal to supply the advanced long-range missile systems to Iran, linking the decision to UN sanctions. President Vladimir Putin lifted the suspension last year following Iran’s nuclear deal with six world powers that curbed its nuclear program in exchange for relief from international sanctions.

Rogozin said Iran will now drop its lawsuit at a court in Geneva seeking damages for the suspension of the original deal.

The S-300 deal has long worried the US and Israel, which see it as destabilizing.

After the Kremlin announced the sale of the advanced system to Iran a year ago, Prime Minister Benjamin Netanyahu spoke with Russian President Vladimir Putin and expressed Israel’s “grave concerns” regarding the Russian decision to sell the surface-to-air missiles.

The Israeli leader told Putin that this sale will “only encourage Iranian aggression in the region” and “further undermine the stability of the Middle East.”

The Kremlin reports that Putin defended the sale, positing that the missiles were only of a defensive nature. Putin “thoroughly explained the Russian leadership’s logic in that context, emphasizing the fact that the S-300 is a purely defensive system that wouldn’t jeopardize security of Israel or any other countries of the Middle East,” the Kremlin stated.

The S-300 is one of the most advanced air defense systems in the world, designed to intercept aircraft, cruise and ballistic missiles.

Iran’s acquisition of the surface-to-air missiles will make an aerial attack on Iran by the US or Israel a much more complex and dangerous task.

By: AP and United with Israel Staff