President Dmitry Medvedev said Israel had given Russia assurances it plans no strike on Iran and reserved Moscow's right to sell Tehran arms, in an interview released by the Kremlin yesterday.
Mr Medvedev described an Israeli attack as "the worst thing that could be imagined" but said President Shimon Peres had ruled out such fears when the two leaders met in the Russian resort of Sochi last month.
"When Israeli President Peres was visiting me in Sochi recently, he said something very important for all of us: 'Israel does not plan any strikes on Iran, we are a peaceful country and we will not do this'," he said.
In the interview with CNN, Mr Medvedev sidestepped questions on Russia's possible response in the case of Israeli air strikes although he hinted Moscow could take sides under such a scenario.
"What will happen after that? Humanitarian disaster, vast numbers of refugees, Iran's wish to take revenge not only on Israel but upon other countries as well," he said.
Though Russia has no alliances with Iran, "It does not mean that we would like to be or will be indifferent to such a development," Mr Medvedev said.
"But my Israeli colleagues told me that they were not planning to act in this way," he reiterated.
Iran is due to hold talks with six world powers on October 1, the outcome of which could determine whether the US and its allies impose more penalties on Tehran over suspicions it is working on an atomic bomb.
The US is pressuring Russia to shift its current stance and back tougher sanctions, reportedly banking on its warming ties with Moscow since President Barack Obama shelved controversial missile shield plans in central Europe.
While Tehran insists its nuclear programme is peaceful, Washington and Israel have also never ruled out the option of air strikes to destroy the Islamic state's nuclear facilities.
Ahead of the Iran talks, Mr Medvedev confirmed that Israeli Prime Minister Benjamin Netanyahu made a secret visit to Moscow this month to meet with him.
"Prime Minister Netanyahu has visited Moscow. They did this in a closed regime, this was their decision," the Russian President said.
Media reported that Mr Netanyahu had flown to Russia on September 7 to pressure Moscow not to deliver advanced missile systems to its arch-foe Iran.
Russia reportedly sold Iran S-300 anti-aircraft missile systems under a contract signed in 2005 but has delayed delivery amid Western fears the systems could destabilise the security balance in the region.
Mr Medvedev however reserved Russia' right to sell Iran defensive arms. "Our relations with Iran have a military component," he said. "What we have supplied and are going to supply has always been defensive weapons' systems."
"I will hold to this when making final decisions as to the all existing contracts with Iran," Mr Medvedev added.
Israel has for years tried to convince Russia not to sell Tehran the S-300 missiles, which the Jewish state fears Iran could use to rebuff a strike against its controversial nuclear sites.
While Mr Medvedev acknowledged Israel's concerns, he said "supplies of any weapons, particularly defensive ones, cannot increase the tension. On the contrary, they should ease them."
UN Security Council member Russia is helping build Tehran's first civilian nuclear power plant at Bushehr and has long defended Iran against calls for tougher sanctions.