Iran urged Russia yesterday not to bow to Western pressure over the sale of a Russian missile defence system to the Islamic Republic which could protect its nuclear facilities from air strikes.

A cleric in the Revolutionary Guards again warned Iran would hit back with missiles fired at "the heart of Tel Aviv" if it were attacked by its arch-foe Israel.

Russia is under intense Western pressure to distance itself from Iran in a dispute over Teheran's nuclear programme, but has refused to rule out delivering the S-300 anti-aircraft system. Iranian officials have expressed growing irritation at Russia's failure so far to supply the S-300, which Israel and the United States do not want Teheran to have.

"Iran expects Russia not to be influenced and pressured by other countries," Foreign Ministry spokes-man Ramin Mehmanparast told a news conference.

"We hope this issue will reach a conclusion in the framework of our agreements," he said.

Analysts say the S-300 could help Iran thwart any attempt by Israel or the United States - which have refused to rule out military action if diplomacy fails to resolve the atomic row - to bomb its nuclear facilities.

The truck-mounted S-300PMU1, known in the West as the SA-20, can shoot down cruise missiles and aircraft. It has a range of 150 km and travels at more than two km per second.

Washington is seeking support from Russia for tougher UN sanctions against Iran over its nuclear programme, which the West suspects is intended to produce nuclear weapons. Tehran says it is for power generation only.