The Kremlin warned on Friday that the Middle East was plunging into "an abyss of instability and war" and said Moscow was worried by events and still stood ready to mediate.
Russia, which has warm ties with Iran and also maintains close links to Israel, has urged the US not to strike Iran and has called for a diplomatic solution to the crisis around Tehran's nuclear program to be found.
Asked on Friday if Russia had any red lines when it came to the situation, Kremlin spokesman Dmitry Peskov told reporters that countries in the region were the ones who should have their own red lines.
"The region is plunging into an abyss of instability and war," Peskov said.
"This war is fraught with (the risk of) geographic expansion and unpredictable consequences. This region is at our borders. It's potentially dangerous for us and we are concerned."
Although Russia does not border any country in the Middle East its southern North Caucasus region borders a belt of former Soviet republics which in turn border Iran and Türkiye.
Peskov said that Moscow observed for now that Israel wanted to continue its military action against Iran, but said Russia has lines of communication open with Israel, the US and Iran.
Peskov said it was hard to predict whether an offer by President Vladimir Putin to mediate in the crisis would be taken up or not, but said that Moscow favored an end to hostilities and a move to diplomacy as soon as possible.
Russian nuclear energy chief Alexei Likhachev said the situation at Iran's Bushehr nuclear power plant, where hundreds of Russian specialists work, was "normal" and under control.
The Israeli military said at one point on Thursday that it had struck the Russian-built Bushehr facility, but later said the comment had been made by mistake. Likhachev, head of the state nuclear energy corporation Rosatom, said on Thursday that any attack on the plant could cause a Chernobyl-style nuclear disaster.
On Friday he told reporters in St Petersburg: "We...very much hope that all our signals from yesterday reached the Israeli leadership."
Likhachev said Russia has just over 300 staff at Bushehr and a total presence of about 500 people, including family members.
