"Iran is already well on its way to controlling Iraq, Yemen and to a large extent is already in practice in control of Lebanon," Netanyahu told Russian President Vladimir Putin as they met in Russia's Black Sea resort of Sochi on Wednesday.

The visiting PM, who was hoping for a sympathetic response from Putin, was left disappointed as the Russian head of state refused to address his claims.

But later in the day, Russian Ambassador to the UN Vasily Nebenzya dismissed the Israeli prime minister's claims.

"We know Israel's position on Iran, but we believe that Iran plays a very constructive role in Syria," the Russian envoy stated.

We have been working closely with Iran to bring an end to the conflict in Syria as soon as possible, Nebenzya added.

Russia and Iran have helped the government of Syrian President Bashar al-Assad score major victories in the years-long fight against foreign-backed terror groups in the conflict-ridden Arab country.

Moscow has been running an aerial campaign against terror positions across Syria since 2015.

It has also separately pushed through with a plan alongside Iran and Turkey to set up four de-escalation zones throughout Syria, where airstrikes would be halted.