Many times Moscow and Tehran seemed like best friends but really they are more suspicious neighbors than partners. So, right now Iran have filed a $4-billion lawsuit against Moscow with the International Court of Arbitration. Tehran accused Moscow of reneging on a contract to deliver the S-300 anti-aircraft missile systems two years ago Apparently, Iran wants to protect itself completely from a potential war and allegeable US invasion. But at the other site Iran has a nuclear contract with Russia (Bushehr energy plant) and so, Moscow has another lever of influence on it. That is not an easy situation for peacetime, but who know what will Moscow do if the armed conflict starts? Main idea is successfully stolen from www.valdaiclub.com
Tehran and Russia have never never had a good relationship, from the Russo-Persian Wars in the 1700's and 1800's, to the bad relations during the Communist times (Iran imprisoned communists and executed Iranians who illegally went to Russia and later returned). In turn, the Soviet Union supplied arms to Iraq that were used to slaughter poorly equipped Iranians defending their country during the Iraq-Iran war. But in the last few decades, Russia has been selling weapons and nuclear technology to Iran.
