The growing influence of Iran in Syria is a threat to Israel, the Middle East and the world, Israeli prime minister Benjamin Netanyahu told Russian president Vladimir Putin on Wednesday.
"Iran is putting in great efforts to fortify its presence in Syria. This is a threat for Israel, for the Middle East and, I believe, for the whole world," Mr Netanyahu said when they met in Sochi, Russia's Black Sea resort.
"With joint efforts we are defeating Islamic State, and this is a very important thing. But the bad thing is that where the defeated Islamic State group vanishes, Iran is stepping in," he said.
Russia intervened in Syria on behalf of president Bashar Al Assad in 2015, whose regime is strongly supported by Iran.
Mr Netanyahu also opposed a ceasefire brokered by Moscow and Washington in south-west Syria last month over Iranian presence there.
Moscow has also been the main broker for Syria's de-escalation zones in recent months, but Israel is concerned such areas will allow Iranian troops and Hizbollah forces to deploy in greater strength.
Russia argues its big-power clout deters Iran or Hizbollah from opening a new front with Israel.
"Iran is already well on its way to controlling Iraq, Yemen and to a large extent is already in practice in control of Lebanon," Mr Netanyahu said.
But Mr Putin did not address Mr Netanyahu's remarks about Iran's growing influence during the meeting which reporters were allowed to attend.
"We cannot forget for a single minute that Iran threatens every day to annihilate Israel," Mr Netanyahu said. "It [Iran] arms terrorist organisations, it sponsors and initiates terror."
Iran denies sponsoring terrorism.
Since Syria's civil war erupted in 2011, Israel has maintained a policy of attacking arms convoys intended for its Lebanese arch-foe Hizbollah, which backs the Assad regime and fought a devastating war against Israel in 2006.
Israel seized 1,200 square kilometres of the Golan Heights from Syria in the 1967 Arab-Israeli war. It was later annexed in a move never recognised by the international community.
About some 500 square kilometres of the area is under Syrian control.
Israel and Iran regularly accuse each other of being a threat to stability in the region.
In comments published last week, the Israel air force chief said Israel had struck suspected Hizbollah arms shipments in Syria around 100 times during the Syrian civil war, apparently without Russian interference and rarely drawing retaliation.