Russian President Vladimir Putin has said that the nuclear collaboration between his country and Iran is merely for "peaceful uses" of atomic energy.
Mr Putin says Iran should be allowed to use modern technology
Mr Putin was talking to Israel's Channel 1 ahead of a historic trip to Israel - the first by a Russian leader.
He also said Russian missiles sold to Syria would not fall into the hands of anti-Israeli militants.
Israeli Prime Minister Ariel Sharon is expected to express his concerns over the weapons during Mr Putin's visit.
"Our position on nuclear non-proliferation is consistent and strict - we are categorically against proliferation of nuclear weapons and categorically against any kind of military nuclear programmes in Iran," the president said.
He went on to say that the programme was being monitored by the IAEA (International Atomic Energy Agency), and that agreements had been amended "to make sure that our partners are not using this cooperation for military purposes".
But he also stressed the need to respect Iran's right to develop peaceful modern technology and to safeguard "their scientific and economic interests".
"Iran must not feel itself discriminated insofar as modern scientific achievements and technologies are concerned," he said.
Monitoring the weapons
Israel and the US oppose a Russian-Iranian project to build a nuclear power plant at Bushehr, in southern Iran, for fear the facility might be used to build nuclear weapons.
Mr Putin also dismissed concerns that short-range, anti-aircraft missiles sold by Moscow to Syria might be used by Palestinian groups or the Lebanese guerrilla group Hezbollah against Israel.
"(The weapons) cannot be transferred to terror organisations without someone finding out," he told Israeli television.
"We have the capabilities to monitor them."
Mr Putin then admitted that the missiles would make it difficult fly over Syria's presidential residence at low altitude.
"These systems can hit a target within the visibility range. They are mounted on vehicles and cannot be secretly passed on to terrorist organisations.
"But I am not sure that these flights are correct if all of us, including Israel acting in the interests of its own people, want to create a favourable atmosphere for the further peace process," Mr Putin was quoted as saying by Russia's Itar-Tass news agency.