Russia sees no reason to stall on the sale of its S-300 anti-aircraft systems to Iran, the Kremlin's powerful Security Council said yesterday, hours before the premier of Iran's adversary Israel was due to visit Moscow.

The possible sale of Russian air defence hardware to the Islamic Republic is a major irritant for both Israel and close ally the United States.

Both have pressed Moscow not to go ahead with a deal that may help protect Iran's nuclear facilities from potential air strikes.

"There is a signed contract (to supply S-300 missiles) which we must implement, but deliveries have not started yet," Vladimir Nazarov, deputy secretary of Russia's Security Council, told Interfax news agency in an interview.

"This deal is not restricted by any international sanctions, because the talk is about deliveries of an exclusively defensive weapon," he said.

Mr Nazarov also said a military strike on Iran would be a big mistake and that the problems linked to Iran's nuclear programme must be resolved only by diplomatic means.

"Any military action against Iran will explode the situation, will have extremely negative consequences for the entire world, including for Russia, which is a neighbour of Iran," he said.

It was a separate issue that Russia's actions should help strengthen international and regional security, respect international law and international commitments including those within the Non-Proliferation Treaty, Mr Nazarov said.

Israeli Prime Minister Benjamin Netanyahu is holding talks with Russian President Dmitry Medvedev in Moscow today, planning to push the Kremlin for urgent "crippling sanctions" against Iran over its nuclear programme.

Mr Medvedev chairs the Security Council.

"Israel believes that heavy pressure must be applied on Iran - above all very severe sanctions, which were referred to by the US secretary of state as 'crippling sanctions'," Mr Netanyahu told the weekly Cabinet meeting earlier yesterday.